CENTER FOR BEHAVIORAL HEALTH STATISTICS AND QUALITY

Drug Abuse Warning Network, 2010:
National Estimates of Drug-Related
Emergency Department Visits

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Substance Abuse and Mental Health Services Administration
Center for Behavioral Health Statistics and Quality

ACKNOWLEDGMENTS

This report was prepared for the Substance Abuse and Mental Health Services Administration (SAMHSA) by RTI International (a trade name of Research Triangle Institute, Research Triangle Park, NC) under contract number HHSS283200700002I, with SAMHSA, U.S. Department of Health and Human Services (HHS). Rong Cai served as the Government Project Officer.

PUBLIC DOMAIN NOTICE

All material appearing in this publication is in the public domain and may be reproduced or copied without permission from SAMHSA. Citation of the source is appreciated. However, this publication may not be reproduced or distributed for a fee without the specific, written authorization of the Office of Communications, SAMHSA, HHS.

RECOMMENDED CITATION

Substance Abuse and Mental Health Services Administration, Drug Abuse Warning Network, 2010: National Estimates of Drug-Related Emergency Department Visits. HHS Publication No. (SMA) 12-4733, DAWN Series D-38. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2012.

ELECTRONIC ACCESS

This publication may be downloaded from https://store.samhsa.gov. Or please call SAMHSA at

1-877-SAMHSA-7 (1-877-726-4727)
(English and Español).

ORIGINATING OFFICE

Center for Behavioral Health Statistics and Quality
Substance Abuse and Mental Health Services Administration
1 Choke Cherry Road, Rockville, MD 20857

November 2012

CONTENTS

Highlights
All Drug-Related ED Visits
Overall Drug Misuse or Abuse
Illicit Drugs
Drugs and Alcohol Taken Together
Underage Drinking
Nonmedical Use of Pharmaceuticals
Drug-Related Suicide Attempts
Seeking Detox Services
Adverse Reactions to Pharmaceuticals
Accidental Ingestion of Drugs

1. Introduction
1.1 Major Features of DAWN
1.1.1 What Is a DAWN Case?
1.1.2 What Drugs Are Included in DAWN?
1.1.3 What Is Covered in This Publication?
1.2 Hospital Participation in 2010
1.3 Estimates of ED Visits
1.4 Rates of ED Visits per 100,000 Population
1.5 Sampling Error
1.6 Suppression
1.7 Comparisons Across Years
1.8 Limitations of the Data

2. Overall Drug Misuse or Abuse
2.1 ED Visits Involving Overall Drug Misuse or Abuse, 2010
2.2 Trends in ED Visits Involving Drug Misuse or Abuse, 2004–2010

3. Illicit Drugs
3.1 ED Visits Involving Illicit Drugs, 2010
3.2 Trends in ED Visits Involving Illicit Drugs, 2004–2010

4. Alcohol
4.1 ED Visits Involving Drugs and Alcohol Taken Together, 2010
4.2 Underage Drinking
4.3 Trends in ED Visits Involving Alcohol, 2004–2010

5. Nonmedical Use of Pharmaceuticals
5.1 ED Visits Involving Nonmedical Use of Pharmaceuticals, 2010
5.2 Trends in ED Visits Involving Nonmedical Use of Pharmaceuticals, 2004–2010

6. Drug-Related Suicide Attempts
6.1 ED Visits Involving Drug-Related Suicide Attempts, 2010
6.2 Trends in ED Visits Involving Drug-Related Suicide Attempts, 2004–2010

7. Seeking Detox Services
7.1 ED Visits Involving Seeking Detox Services, 2010
7.2 Trends in ED Visits Involving Seeking Detox Services, 2004–2010

8. Adverse Reactions to Pharmaceuticals
8.1 ED Visits Involving Adverse Reactions to Pharmaceuticals, 2010
8.2 Trends in ED Visits Involving Adverse Reaction to Pharmaceuticals, 2005–2010

9. Accidental Ingestion of Drugs
9.1 ED Visits Involving Accidental Ingestion of Drugs, 2010
9.2 Trends in ED Visits Involving Accidental Ingestion of Drugs by Patients Aged 5 and Under, 2004–2010

List of Tables

Table 1. DAWN analytic groups
Table 2. ED visits involving drug misuse or abuse, by drug combinations, 2010
Table 3. Trends in ED visits involving drug misuse or abuse, by drug combinations, 2004–2010
Table 4. ED visits involving illicit drugs, 2010
Table 5. Rates of ED visits per 100,000 population involving illicit drugs, 2010
Table 6. ED visits involving illicit drugs, by patient demographics, 2010
Table 7. Rates of ED visits per 100,000 population involving illicit drugs, by patient demographics, 2010
Table 8. ED visits and rates involving illicit drugs, by patient disposition, 2010
Table 9. Trends in ED visits involving illicit drugs, by selected drugs, 2004–2010
Table 10. ED visits involving alcohol, 2010
Table 11. ED visits involving drugs and alcohol taken together, 2010
Table 12. ED visits involving drugs and alcohol taken together, by selected drugs, 2010
Table 13. ED visits involving drugs and alcohol taken together, by patient demographics, 2010
Table 14. ED visits involving drugs and alcohol taken together, by patient disposition, 2010
Table 15. ED visits involving underage drinking, 2010
Table 16. ED visits involving alcohol, by patients aged 12 to 17 and 18 to 20, 2010
Table 17. Trends in ED visits involving alcohol, 2004–2010
Table 18. ED visits involving nonmedical use of pharmaceuticals, by selected drugs, 2010
Table 19. ED visits and rates involving nonmedical use of pharmaceuticals, by patient demographics, 2010
Table 20. ED visits and rates involving nonmedical use of pharmaceuticals, by patient disposition, 2010
Table 21. Trends in ED visits involving nonmedical use of pharmaceuticals, by selected drugs, 2004–2010
Table 22. ED visits involving drug-related suicide attempts, by selected drugs, 2010
Table 23. ED visits involving drug-related suicide attempts, by patient demographics, 2010
Table 24. ED visits involving drug-related suicide attempts, by patient disposition, 2010
Table 25. Trends in ED visits for drug-related suicide attempts, by selected drugs, 2004–2010
Table 26. ED visits involving seeking detox services, by selected drugs, 2010
Table 27. ED visits involving seeking detox services, by patient demographics, 2010
Table 28. ED visits involving seeking detox services, by patient disposition, 2010
Table 29. Trends in ED visits involving seeking detox services, by selected drugs, 2004–2010
Table 30. ED visits involving adverse reaction to pharmaceuticals, 2010
Table 31. ED visits and rates involving adverse reaction to pharmaceuticals, by patient demographics, 2010
Table 32. ED visits and rates involving adverse reaction to pharmaceuticals, by patient disposition, 2010
Table 33. Trends in ED visits involving adverse reaction to pharmaceuticals, by selected drugs, 2005–2010
Table 34. ED visits involving accidental ingestion of drugs by patients aged 5 and under, 2010
Table 35. ED visits and rates involving accidental ingestion of drugs by patients aged 5 and under, by patient demographics, 2010
Table 36. ED visits and rates involving accidental ingestion of drugs by patients aged 5 and under, by patient disposition, 2010
Table 37. Trends in ED visits involving accidental ingestion of drugs by patients aged 5 and under, by selected drugs, 2004–2010

List of Figures

Figure 1. Rates of drug-related ED visits per 100,000 population, by age group, 2010
Figure 2. Rates of ED visits per 100,000 population involving illicit drugs, 2010
Figure 3. Rates of ED visits per 100,000 population involving illicit drugs, by selected drugs, age, and sex, 2010
Figure 4. Rates of ED visits per 100,000 population involving alcohol, by age and sex, 2010
Figure 5. Rates of ED visits per 100,000 population involving alcohol, by patients aged 12 to 17 and 18 to 20, 2010
Figure 6. Rates of ED visits per 100,000 population involving nonmedical use of pharmaceuticals, by age and sex, 2010
Figure 7. Rates of ED visits per 100,000 population involving drug-related suicide attempts, by age and sex, 2010
Figure 8. Rates of ED visits per 100,000 population involving seeking detox services, by age and sex, 2010
Figure 9. Rates of ED visits per 100,000 population involving adverse reaction to pharmaceuticals, by age and sex, 2010
Figure 10. Rates of ED visits per 100,000 population involving accidental ingestion of pharmaceuticals, by age, 2010

List of Attachments

Attachment A. Glossary of DAWN Terms, 2010 Update
Attachment B. Drug Abuse Warning Network Methodology Report, 2010 Update
Attachment C. Guide to Drug Abuse Warning Network Trend Tables, 2010 Update

HIGHLIGHTS

This publication presents national estimates of drug-related visits to hospital emergency departments (EDs) for the calendar year 2010, based on data from the Drug Abuse Warning Network (DAWN). Also presented are comparisons of 2010 estimates with those for 2004, 2008, and 2009. DAWN is a public health surveillance system that monitors drug-related ED visits for the Nation and for selected metropolitan areas. The Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services (HHS), is the agency responsible for DAWN. SAMHSA is required to collect data on drug-related ED visits under section 505 of the Public Health Service Act.

DAWN relies on a nationally representative sample of general, non-Federal hospitals operating 24-hour EDs, with oversampling of hospitals in selected metropolitan areas. In each participating hospital, ED medical records are reviewed retrospectively to find the ED visits that involved recent drug use. All types of drugs—illegal drugs, prescription drugs, over-the-counter pharmaceuticals (e.g., dietary supplements, cough medicine), and substances inhaled for their psychoactive effects—are included. Alcohol is considered an illicit drug when consumed by patients aged 20 or younger. For patients aged 21 or older, though, alcohol is reported only when it is used in conjunction with other drugs.

Marked findings of this report are (a) a 94 percent increase in the number of drug-related ED visits overall between 2004 and 2010, and (b) large increases in the involvement of a wide range of pharmaceuticals (e.g., prescription drugs, over-the-counter medications, supplements) over that period. It is likely that there are multiple causes contributing to these increases. Some portion of these increases may be associated with the greater number of prescriptions being written and with more people taking multiple prescription drugs, often in combination with over-the-counter preparations, as part of their long-term medical care. The greater availability of prescription drugs also facilitates their diversion for intentional misuse as well as accidental ingestion. It is beyond the scope of this report, though, to explore more fully the causes behind the growing numbers of ED visits involving pharmaceuticals, and further analysis is needed.

All Drug-Related ED Visits

In 2010, over 125 million visits were made to EDs in general-purpose, non-Federal hospitals operating 24-hour EDs in the United States. DAWN estimates that just under 5 million of these visits, or 1,589.0 ED visits per 100,000 population, were related to drugs, a 94 percent increase since 2004. In 2010, drug-related visits range from a high of 2,478.3 visits per 100,000 population aged 18 to 20 to a low of 263.3 visits per 100,000 population aged 6 to 11 (Figure 1).

Figure 1.
Rates of drug-related ED visits per 100,000 population, by age group, 2010

   D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.

Overall Drug Misuse or Abuse

In 2010, DAWN estimates that about 2.3 million ED visits resulted from medical emergencies involving drug misuse or abuse, the equivalent of 743.7 ED visits per 100,000 population. For those aged 20 or younger, the rate is 476.1 visits; for those aged 21 or older, the rate is 849.4 visits.

Understanding that a visit may appear in more than one group, DAWN found that out of all drug misuse or abuse ED visits,

• 1,173,654 ED visits, or 51.0 percent, involved nonmedical use of pharmaceuticals;
• 1,171,024 ED visits, or 50.9 percent, involved illicit drugs; and
• 687,574 ED visits, or 29.9 percent, involved alcohol.

Although the overall number of ED visits attributable to drug misuse or abuse was stable from 2004 to 2010, ED visits related to the use of pharmaceuticals with no other drug involvement rose substantially (132% increase), as did the use of pharmaceuticals with illicit drugs (139% increase), pharmaceuticals with alcohol (63% increase), and pharmaceuticals combined with both illicit drugs and alcohol (94% increase).

Illicit Drugs

DAWN estimates that 1,171,024 ED visits in 2010 involved an illicit drug. That is, 50.9 percent of all the drug misuse or abuse ED visits during the year involved one or more illicit drugs taken alone or in combination with pharmaceuticals, alcohol, or both. Among all visits involving illicit drugs,

• cocaine was involved in 488,101 visits, or 41.7 percent;
• marijuana was involved in 461,028 visits, or 39.4 percent;
• heroin was involved in 224,706 visits, or 19.2 percent;
• amphetamines/methamphetamine were involved in 137,947 visits, or 11.8 percent;
• PCP was involved in 53,542 visits, or 4.6 percent; and
• other illicit drugs—such as PCP, MDMA ("Ecstasy"), synthetic cannabinoids, inhalants, hallucinogens, LSD, GHB, ketamine, and flunitrazepam (e.g., Rohypnol^®)—were each involved in fewer than 2.0 percent.

Synthetic cannabinoids, also known as "Spice" or "K2," appeared for the first time at reportable levels in DAWN in 2010; they were involved in 11,406 ED visits (1.0%).

In 2010, there were 378.5 ED visits that involved illicit drugs for each 100,000 persons in the U.S. population. The highest rates were found for cocaine involvement (157.8 ED visits per 100,000 population) and marijuana (149.0 visits), followed by heroin (72.6 visits), amphetamines/methamphetamine (44.6 visits), PCP (17.3 visits), Ecstasy (7.1 visits), inhalants (3.7 visits), and synthetic cannabinoids (3.7 visits). Lower-incidence drugs had rates below 2 visits per 100,000 population.

For most illicit drugs, including cocaine, heroin, marijuana, and amphetamines/methamphetamine, the rate was higher for males than for females. Looking across age categories, the rate of marijuana involvement was highest for patients aged 18 to 20 (529.3 visits per 100,000 population), and cocaine was highest for those aged 35 to 44 (327.6 visits). Heroin and amphetamines/methamphetamine involvement was highest for those aged 25 to 29 (186.9 and 124.3 visits per 100,000 population, respectively).

Overall, 40.9 percent of visits involving illicit drugs resulted in some form of follow-up, including admission to the hospital (23.9%), transfer to another health care facility (10.8%), or referral to a detox/dependency program (6.3%). Most other patients (48.1%) were treated and released to home, with the remainder (11.0%) experiencing other outcomes.

While the overall level of ED visits involving illicit drugs from 2004 to 2008 was stable, DAWN observed an 18 percent increase in illicit drug–related visits between 2008 and 2010. Contributing to that rise were visits involving cannabinoids (including marijuana and synthetic cannabinoids), which increased 26 percent between 2008 and 2010, and visits involving amphetamines/methamphetamine, which increased 50 percent. The balance of amphetamines versus methamphetamine visits has shifted over the period from 2004 to 2010. In 2004, there were almost four methamphetamine-involved visits for every amphetamines-related visit; in 2010, there were fewer than two.

Drugs and Alcohol Taken Together

In 2010, over half a million ED visits, or 24.5 percent of all drug misuse or abuse ED visits, involved drugs combined with alcohol. The rate of alcohol-related ED visits per 100,000 population for males (240.1 visits) was higher than that for females (126.7 visits). The highest level was seen for patients aged 21 to 24 (354.6 visits).

Almost half (46.2%) of patients received some sort of follow-up care: 28.6 percent were admitted to the hospital, 11.7 percent were transferred to another facility, and 5.9 percent were referred to detox. The remaining patients were treated and released to home (44.9%) or had other outcomes (8.9%).

Illicit drugs were involved in over half (59.8%) of ED visits involving alcohol and other drugs, with cocaine or marijuana representing the greatest proportion of such visits (30.2% and 26.7%, respectively). One or more pharmaceuticals were also involved in over half (55.8%) of these visits. Pain relievers were observed in 23.0 percent of visits, with narcotic pain relievers accounting for over half of that (14.0%). Drugs for insomnia and anxiety were involved in 23.1 percent of visits, with the largest part of that being benzodiazepines (19.7%). Psychotherapeutic agents (antidepressants and antipsychotics) were involved in less than 8 percent of visits involving alcohol-drug combinations.

Between 2004 and 2010, involvement of alcohol in drug misuse or abuse ED visits remained stable.

Underage Drinking

There were over 189,060 medical emergencies involving alcohol for patients aged 20 or younger in 2010, representing almost half (45.2%) of all drug misuse or abuse ED visits made by patients aged 20 or younger. The rate of medical emergencies involving the abuse of alcohol by youths was 291.0 visits per 100,000 population aged 12 to 17 and 848.7 visits per 100,000 population aged 18 to 20, almost a threefold difference. The pattern is similar when looking at ED visits for either alcohol alone or alcohol used in combination with other drugs. Between 2004 and 2010, levels of ED visits involving underage drinking remained constant for youth aged 12 to 17 and young adults aged 18 to 20.

Nonmedical Use of Pharmaceuticals

There is growing concern in the public health community about the misuse of pharmaceuticals. For 2010, DAWN estimates that 1,173,654 ED visits involved nonmedical use of prescription medicines, over-the-counter drugs, or other types of pharmaceuticals. This represents about a quarter (23.9%) of all drug-related ED visits and over half (51.0%) of ED visits for drug misuse or abuse. Over half (54.7%) of ED visits resulting from nonmedical use of pharmaceuticals involved multiple drugs, and about one in five (17.4%) involved alcohol.

Visits for nonmedical use of pharmaceuticals did not differ significantly between males and females (374.2 and 383.9 visits per 100,000 population, respectively). On the other hand, notable differences were seen between age categories: rates for patients aged 21 to 34 were over 600 visits per 100,000 population, with lower levels observed for younger and older patients.

Almost 40 percent (37.4%) of patients misusing pharmaceuticals received some form of follow-up care, including referral to detox/treatment (2.4%), admission to the hospital (25.5%), or transfer to another facility (9.5%). Of the remaining patients, most were treated and released to home (54.0%) or had other outcomes (8.6%).

The most common type of drug involved in ED visits for the nonmedical use of pharmaceuticals was pain relievers (48.3%), with the highest levels seen for the narcotic pain relievers oxycodone, hydrocodone, and methadone (12.5%, 8.2%, and 5.6%, respectively). Drugs used to treat anxiety and insomnia were also seen frequently (34.0%) in visits related to the misuse of pharmaceuticals. Of these, benzodiazepines accounted for the majority (29.5%) of these ED visits, specifically alprazolam (e.g., Xanax^®), which was indicated in about a third (10.6%) of visits involving benzodiazepines.

From 2004 to 2010, medical emergencies related to the nonmedical use of pharmaceuticals increased 119 percent. Contributing to this rise was the 149 percent increase in the number of visits involving narcotic pain relievers. Specific narcotic drugs that more than doubled their involvement in ED visits between 2004 and 2010 were fentanyl, hydrocodone, hydromorphone, morphine, and oxycodone. Visits involving tramadol (e.g., Ultram^®), a narcotic-like opiate agonist used for moderate-to-severe pain, increased 235 percent.

Between 2004 and 2010, the number of visits involving drugs for anxiety and insomnia increased 125 percent. Involvement of drugs in the benzodiazepine family experienced a 141 percent increase. Zolpidem (e.g., Ambien^®), a sleeping aid with benzodiazepine-like properties, increased 150 percent. Muscle relaxants (e.g., carisprodol, cyclobenzaprine) increased 107 percent. The attention deficit hyperactivity disorder (ADHD) drug amphetamine-dextroamphetamine (e.g., Adderall^®) saw a 392 percent increase between 2004 and 2010.

Drug-Related Suicide Attempts

Substance abuse is strongly associated with suicide attempts. DAWN estimates that there were 212,736 medical emergencies resulting in ED visits for drug-related suicide attempts in 2010. Almost all (94.7%) of these ED visits involved a prescription drug or over-the-counter medication; about two thirds (62.6%) involved multiple drugs; about a quarter (25.3%) involved alcohol; and about a fifth (17.8%) involved illicit drugs.

Pharmaceuticals were much more common than illicit drugs in ED visits for drug-related suicide attempts. More than a third (37.1%) of these visits involved pain relievers, with narcotic pain relievers accounting for almost half that number (15.5%). Benzodiazepines were involved in more than a quarter (28.4%) of visits, with alprazolam accounting for about a third of that number (10.6%). Antidepressants were involved in 19.9 percent of ED visits for drug-related suicide attempts, with about half (10.5%) of these involving SSRI antidepressants such as sertraline (e.g., Zoloft^®), fluoxetine (e.g., Prozac^®), and citalopram (e.g., Celexa^®).

The rate of drug-related suicide-attempt visits for females (80.8 visits per 100,000 population) was higher than that for males (56.3 visits per 100,000). With regard to age, rates ranged from 13.4 visits per 100,000 population for those aged 65 or older to 160.1 visits per 100,000 population for those aged 18 to 20.

Following the ED visit, 77.8 percent of patients who attempted suicide received some form of follow-up care. About half (49.9%) were admitted for inpatient hospital care, with 17.9 percent admitted to intensive or critical care units (ICUs) and 12.7 percent admitted to psychiatric units. A quarter (24.8%) of patients were transferred to another health care facility, and 3.0 percent were discharged with a referral to detox or substance abuse treatment services. The remaining patients (22.2%) were treated and released to home or had other dispositions.

The number of drug-related suicide attempts remained stable from 2004 to 2010. However, the involvement of narcotic pain relievers increased 95 percent during this time. Specifically, hydrocodone (e.g., Vicodin^®) and oxycodone (e.g., OxyContin^®) increased 83 percent and 147 percent, respectively. There was also a 53 percent rise observed between 2004 and 2010 for drugs used to treat anxiety and insomnia. Benzodiazepine involvement, in general, rose 63 percent, with substantial increases observed for alprazolam (e.g., Xanax), clonazepam (e.g., Klonopin^®), lorazepam (e.g., Ativan^®), and zolpidem (e.g., Ambien).

Seeking Detox Services

The category of visits referred to as "seeking detox" includes nonemergency requests for admission for detoxification, visits to obtain medical clearance before entry to a detox program, and acute emergencies in which an individual who is experiencing withdrawal symptoms is seeking detox. DAWN estimates that there were 232,542 drug-related ED visits for patients seeking detox or substance abuse treatment services during 2010. Visits for more than two thirds (67.8%) of patients seeking detox involved multiple drugs, and 29.8 percent involved alcohol.

Males were more likely than females to seek detox services (99.2 and 51.9 visits per 100,000 population, respectively). Rates of visits for patients seeking detox peaked at 206.7 visits per 100,000 population for those aged 21 to 24.

More than half (58.1%) of ED patients seeking detox obtained some form of follow-up: 32.2 percent were admitted to the hospital, 17.3 percent were referred to detox/treatment services, and 8.6 percent were transferred to another facility. The remaining patients were treated and released to home (31.1%) or had other outcomes.

As to the types of drugs involved, cocaine was observed in 27.6 percent of visits by patients seeking detox, heroin in 26.7 percent, marijuana in 18.5 percent, and amphetamines/methamphetamine in 5.9 percent. Among pharmaceuticals, narcotic pain relievers were observed in 45.4 percent of visits, including oxycodone at 28.8 percent. Benzodiazepines were observed in 23.1 percent of visits, with alprazolam at 12.2 percent.

The overall number of ED visits by patients seeking detox has not grown significantly since 2004, though pharmaceutical involvement has become more common in recent years. There was a 22 percent increase between 2009 and 2010 in pharmaceutical involvement overall, a 35 percent increase in narcotic pain relievers, and a 47 percent increase in oxycodone.

Adverse Reactions to Pharmaceuticals

Adverse reactions among ambulatory populations are a growing public health concern in the United States because people are being prescribed more drugs and the number of older persons who typically take more medications has increased. In 2010, DAWN estimates that 2,329,221 ED visits involved adverse reactions to prescription medicines, over-the-counter drugs, or other therapeutic substances used as prescribed or indicated. This represents just under half (47.4%) of all drug-related ED visits.

The drugs most commonly involved in adverse reactions, anti-infectives (e.g., antibiotics), were involved in 21.7 percent of visits. As a general category, pain relievers were involved in 16.3 percent of visits, with narcotic pain relievers accounting for 8.9 percent. Cardiovascular agents appeared in 10.4 percent of visits. Coagulation modifiers were involved in 7.9 percent, and metabolic agents, such as insulin and lipid-lowering drugs, were found in 7.6 percent of visits.

When population size and sampling error were taken into account, women had notably more visits than men (909.3 and 590.2 visits per 100,000 population, respectively) involving drug-related adverse reactions. For children aged 5 and under, the rate of ED visits for adverse reactions was 736.0 visits per 100,000 population. The rate dropped to a low of 231.8 visits for children aged 6 to 11 and then rose consistently to reach a high of 1,678.9 visits for patients aged 65 or older. About three quarters (75.6%) of patients were treated and released, a fifth (20.7%) were admitted to the hospital, and the remainder (3.7%) had other outcomes.

Overall, ED visits resulting from adverse reactions to pharmaceuticals increased 86 percent in the period from 2005 to 2010, rising from about 1.3 million visits to over 2.3 million. Noteworthy trends and heavily involved drugs include the following:

• anti-anxiety drugs and sleeping aids – 108 percent increase (e.g., zolpidem, alprazolam, clonazepam, lorazepam);
• antidepressants – 119 percent increase;
• anticonvulsants – 85 percent increase;
• antidiabetic drugs – 87 percent increase (e.g., insulin, biguanides, sulfonylureas);
• anti-infectives – 65 percent increase (e.g., amebicides, cephalosporins, lincomycin derivatives, macrolide derivatives, penicillins, quinolones, sulfonamides, tetracyclines);
• antineoplastics (chemotherapy drugs) – 157 percent increase;
• antipsychotics – 110 percent increase (e.g., quetiapines);
• cardiovascular agents – 108 percent (e.g., ACE inhibitors, beta blockers, calcium channel blockers, diuretics);
• hormone-based drugs – 148 percent increase (e.g., adrenal cortical steroids, sex hormones, thyroid hormones);
• immunological drugs (bacterial and viral vaccines) – 157 percent increase;
• nutritional products – 185 percent increase (e.g., minerals and electrolytes products, oral nutritional supplements, vitamins); and
• pain relievers – 70 percent increase (e.g., hydrocodone and oxycodone products).

Accidental Ingestion of Drugs

Accidental ingestion of drugs by children is an eminently preventable health risk. Nonetheless, poison control centers find that over half of human exposure calls involve children aged 5 and under, and the majority of substances involved in pediatric exposures are drugs. The danger of accidental ingestion of drugs by children is even more apparent in the 2010 DAWN findings, where over two thirds (67.9%) of the 107,632 accidental ingestion ED visits involved children aged 5 and under. DAWN found the rate of ED visits for accidental ingestion by children aged 5 and under to be almost 25 times higher than for adults: 300.2 ED visits per 100,000 children aged 5 and under compared with 12.7 ED visits per 100,000 for adults aged 21 and older. Two-year-olds are at greatest risk, with a rate of 701.1 visits.

Pain relievers, cardiac medications, aspirin products, antidepressants, antidiabetic medications, camphor-containing salves (when ingested), eye drops, and nasal sprays are recognized as being particularly dangerous when accidentally ingested by children. For ED patients aged 5 and under, DAWN found that pain relief medication was the most common class of drugs involved in accidental ingestion, with 28.0 percent of visits. Cardiovascular agents were involved in 13.1 percent of visits, antidepressants in 6.4 percent of visits, and antidiabetic drugs in 2.5 percent. Other drugs DAWN found involved in pediatric poisonings included respiratory agents (e.g., antihistamines, bronchodilators, and a broad range of combination products used to treat upper respiratory conditions; 11.6%); acetaminophen products (10.5%); anxiolytics, sedatives, and hypnotics (drugs to treat insomnia and anxiety; 9.9%); antipsychotics (5.3%); and topical agents (5.3%).

The large majority (83.9%) of accidental ingestion ED patients aged 5 and under were treated and discharged home. About 15 percent received more extensive follow-up care: either admission to the hospital (10.4%), or transfer to another facility (4.2%). Medical emergencies related to accidental ingestions by patients aged 5 and under were stable from 2004 to 2010, though increases were observed for particular drug groups. Involvement of pain relievers in general saw a 70 percent increase since 2004, and involvement of antihistamines rose 162 percent.

1. INTRODUCTION

This publication presents estimates of drug-related emergency department (ED) visits from the Drug Abuse Warning Network (DAWN) for 2010, with comparison of estimates for 2004, 2008, and 2009. DAWN is a public health surveillance system that monitors patients' medical records of ED visits for the Nation to identify those visits that are related to drug use, misuse, and abuse. The Center for Behavioral Health Statistics and Quality (CBHSQ) of the Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services (HHS), has been responsible for DAWN operations since 1992.

This introduction provides a brief description of the major features of DAWN and the statistics presented in this report. Survey findings, as well as comparisons to earlier years' data, are organized in eight following sections, with each section focusing on a specific type of ED visit (as listed in Table 1). Additional details on DAWN terminology and methodology are provided as attachments to this document. Detailed tables of DAWN estimates, this document, its attachments, other reports using DAWN data, and other methodology reports are available at the DAWN Web site.¹ As they become available, DAWN data are accessible through SAMHSA's Data Archive (SAMHDA).²

1.1 Major Features of DAWN

1.1.1 What Is a DAWN Case?

A DAWN case is any ED visit involving recent drug use that is implicated in the ED visit. The reason a patient used a drug is not part of the criteria for considering a visit to be drug related. Therefore, DAWN includes ED visits resulting from accidental ingestions and adverse reactions as well as explicit drug abuse.

1.1.2 What Drugs Are Included in DAWN?

DAWN captures drugs that are explicitly named in the medical record as being involved in the ED visit. The relationship between the ED visit and the drug use need not be causal. That is, an implicated drug may or may not have directly caused the condition generating the ED visit; the ED staff simply named it as being involved. Conversely, DAWN does not report medications or pharmaceuticals that the ED medical records mention as having been taken by the patient but that are unrelated to the ED visit.

Within those guidelines, DAWN collects data on all types of drugs, including the following:

• illegal drugs, e.g., heroin, cocaine, marijuana (including synthetic cannabinoids), MDMA (Ecstasy), PCP, club drugs, ketamine;
• substances that have psychoactive effects when inhaled;
• narcotic pain relievers, e.g., OxyContin, Vicodin;
• prescription drugs for anxiety, depression, sleeplessness, and other behavior disorders, e.g., Xanax, Ritalin^®, Prozac;
• prescription drugs used in the treatment of other medical conditions, e.g., antibiotics, anti-coagulants, insulin, chemotherapy drugs;
• anesthetic gases;
• over-the-counter medications, e.g., acetaminophen, ibuprofen, multi-ingredient cough and cold remedies;
• dietary supplements, e.g., vitamins, herbal remedies, nutritional products;
• alcohol when used in combination with other drugs; and
• alcohol alone, in patients aged 20 or younger.

1.1.3 What Is Covered in This Publication?

This report provides detailed information on ED visits involving drug use, misuse, or abuse for the years 2004 through 2010. The types of ED visits (referred to as analytic groups) highlighted in this publication are listed in Table 1. The analytic groups are defined by the reason for the visit and the types of drugs involved. Because a visit may involve multiple types of drugs (e.g., an illicit drug, such as marijuana, and a pharmaceutical, such as hydrocodone), a single visit may appear in multiple analytic groups.

1.2 Hospital Participation in 2010

DAWN relies on a nationally representative sample of hospitals with oversampling of hospitals in selected metropolitan areas. The universe of hospitals eligible for DAWN includes non-Federal, short-stay, general medical and surgical facilities in the United States that operate 24-hour EDs. DAWN excludes specialty hospitals (e.g., pediatric hospitals), long-term care facilities, and Federal facilities (e.g., Veterans Health Administration hospitals). The American Hospital Association Annual Survey Database (ASDB) was used to identify the original frame members. Subsequent ASDB surveys are used annually to identify "births" of new hospitals that open and "deaths" of hospitals that close or merge with other hospitals.

For 2010, 7.2 million charts out of a universe of 11.6 million charts were reviewed to determine if a visit was drug related. Data on 304,110 drug-related ED visits submitted by 237 hospitals were used for estimation. The overall visit weighted response rate was 34.2 percent.

1.3 Estimates of ED Visits

This publication reports nationally representative estimates of drug-related ED visits for the United States. Estimates are calculated by applying weights and adjustments to the data provided by the sampled hospitals participating in DAWN. The primary sampling weights reflect the probability of hospital selection, and separate adjustment factors are included to account for sampling of ED visits, nonresponse, data quality, and the known total of ED visits delivered by the universe of eligible hospitals, as reported by the most current ASDB survey.

Many of the tables in this report provide estimates of visits, by drug. DAWN is able to identify more than 3,300 individual drugs (which map to more than 19,000 individual brands and street names).³ The more commonly involved drugs and drug categories were selected for inclusion in the drug detail tables appearing in this report. Because (a) a single ED visit may involve multiple drugs, or (b) the same drug may be reported both under its specific drug name and under its drug category, the sum of ED visits from different rows in the drug detail tables will be greater than the total number of visits. For the same reason, percentages will add to more than 100.

1.4 Rates of ED Visits per 100,000 Population

Standardized measures are helpful when comparing levels of drug-related ED visits for different age and sex groups. This publication reports rates of ED visits per 100,000 population by age groups and sex groups per year, e.g., visits in 2010 per 100,000 population aged 12 to 17; visits in 2004 per 100,000 male population. Population estimates are based on counts provided by the U.S. Census Bureau.⁴ Population-based rates for race/ethnicity categories are not reported because race/ethnicity information is often missing from ED records; a dash (—) is displayed instead.

1.5 Sampling Error

Because DAWN relies on a sample of hospitals, each estimate produced from the DAWN ED data is subject to sampling variability, the variation in estimates that would be observed naturally if different samples were drawn from the same population using the same procedures. One measure of sampling variability of an estimate used in this publication is the relative standard error (RSE). The precision of an estimate is inversely related to its RSE. That is, the greater the RSE, the lower the precision. A second measure of sampling error used in this publication is the 95 percent confidence interval (CI). A 95 percent CI means that if repeated samples were drawn from the same population of hospitals using the same sampling and data collection procedures, the true population value would fall within the CI 95 percent of the time. A CI, which is expressed as a range of values, is useful because the interval reflects both the estimate and its particular margin of error. For example, in 2010, there were 2,301,050 ED visits associated with drug misuse or abuse with a CI of 1,987,721 to 2,614,380. The CI indicates with a high degree of confidence that the actual number was within this range.

1.6 Suppression

An asterisk (*) is displayed in the place of suppressed estimates and rates. Data may be suppressed to protect patient confidentiality or to ensure that published findings meet statistical standards of reliability for survey results. In all DAWN published materials, estimates are suppressed according to the following rules:

• The RSE of the estimate is greater than 50 percent. The RSE is a measure of the relative precision and is calculated by dividing the estimate's standard error by the estimate itself. When the RSE is greater than 50 percent, the lower bound of the 95 percent CI approaches or includes the value zero. A CI that includes zero means that the estimate is not statistically different from zero at this precision level.
• The estimate is based on fewer than 30 ED visits. Estimates based on a small number of cases are typically suppressed because the RSE is greater than 50 percent. Estimates that do meet RSE criteria for publication but are based on fewer than 30 ED visits (weighted or unweighted) are deemed too unreliable for publication. Such estimates are also suppressed to protect patient privacy.

Ratios (percentages or rates per 100,000 population) based on suppressed estimates are likewise suppressed.

1.7 Comparisons Across Years

In this publication, between-year changes are assessed by comparing estimates for 2010 with those for 2004, 2008, and 2009.⁵ This publication reports only those between-year changes that are statistically significant at the p < 0.05 level. The p-value is a measure of the probability (p) that the difference between two estimates could have occurred by chance, if the estimates being compared were really the same. The larger the p-value, the more likely the difference could have occurred by chance. For example, if the difference between two DAWN estimates has a p-value of 0.01, it means that there is a 1 percent probability that the difference observed could be due to chance alone.

The redesign of DAWN in 2003 altered most of DAWN's core features. Changes were made to the design of the hospital sample, the protocol for selecting charts to review, the eligibility criteria for being a DAWN case, and the data items submitted on these cases. These changes created a permanent disruption in trends. As a result, comparisons cannot be made between old DAWN (2003 and prior years) and the redesigned DAWN (2004 and forward).

1.8 Limitations of the Data

Readers are advised to consider the following limitations to the DAWN data when interpreting results:

• DAWN data collectors attempt to identify, with a high degree of specificity, the exact drugs involved in an ED visit, but extant medical records vary in specificity and detail. If extant medical records include only a general description of a drug (e.g., "benzodiazepines"), the drug is grouped in a general category (e.g., "benzodiazepines not otherwise specified").
• DAWN relies on the assessment made by ED medical staff to determine which drugs are related to the visit and records only those drugs indicated as being related.
• DAWN does not assess the medical reasons for the visit, and it cannot be assumed that a drug was the direct cause of the medical emergency. For example, a soporific may have caused the patient to fall asleep while driving and then to have an accident.
• Use of illicit drugs is assumed to constitute drug abuse. The determination of nonmedical use of pharmaceuticals, though, must be supported by information provided by medical personnel in the ED records.
• In cases where multiple pharmaceuticals are involved, it is not necessary that both drugs are misused. The medical emergency might stem from the interaction between two pharmaceuticals, one of which was used nonmedically, and the other of which was taken as prescribed.
• While DAWN seeks to report only the drugs that are related to the ED visit, some unrelated drugs may be included if ED records fail to indicate that they were obtained through a legitimate prescription, were taken as prescribed or indicated, and were unrelated to the ED visit. For example, anecdotal evidence suggests that ED records may mention methadone but fail to indicate that the patient was enrolled in a methadone treatment program and that the methadone was unrelated to the medical emergency leading to the ED visit.
• Information on race and ethnicity is often poorly documented in extant ED records. In addition, some hospitals consider race/ethnicity to be private information and will not make it available to DAWN Field Reporters. Overall, about 15 percent of visits each year do not contain race/ethnicity information. DAWN does not produce rates (visits per 100,000 population) for race/ethnicity groups because these missing data will result in the understatement of visits by race/ethnicity category. This might affect racial/ethnic groups differentially and produce misleading findings.
• Although DAWN documents whether a drug was positively confirmed by toxicology testing, DAWN does not require that drugs reported for the ED visit be confirmed by laboratory testing. Toxicology tests are not used consistently across EDs, and some toxicology tests are not specific enough to identify particular drugs. Furthermore, a positive toxicology test is not necessarily evidence of recent drug involvement in an ED visit if it is a current medication or a drug that persists in the system long after it was used. For this reason, DAWN requires that the involvement of drugs be mentioned in the ED record, not just in the toxicology testing results, for the visit to be considered a DAWN case.
• Information on drug-related visits is based on a sample and is therefore subject to sampling variability. Standard error measurements are provided in many tables to reflect the sampling variability that occurs (a) by chance because only a sample rather than the entire universe is surveyed, and (b) due to nonresponse.
• As in any survey, a low response rate is of concern because it creates larger-than-expected sampling errors plus the opportunity for unpredictable biases. DAWN addresses these issues for the short term by always reporting standard errors based on the actual sample of respondents and for the long term by continuing its efforts to raise the hospital participation rate.

2. OVERALL DRUG MISUSE OR ABUSE

2.1 ED Visits Involving Overall Drug Misuse or Abuse, 2010

For 2010, DAWN estimates that there were over 4.9 million drug-related ED visits. Of these, over 2.3 million ED visits were associated with drug misuse or abuse (Table 2). That is the equivalent of 743.7 ED visits for each 100,000 persons in the Nation; for those aged 20 or younger, the rate is 476.1 visits; for those aged 21 or older, the rate is 849.4 visits.

Of the ED visits in 2010 that involved drug misuse or abuse, nearly two thirds (64.6%) were associated with a single drug type (illicit drugs, alcohol, or pharmaceuticals). Illicit drugs alone were involved in 25.3 percent of drug misuse or abuse visits, pharmaceuticals alone were involved in 33.9 percent, and alcohol with no other drug (aged 20 or younger only) was involved in 5.3 percent. The remaining visits (35.4%) involved some combination of illicit drugs, alcohol, and pharmaceuticals.

Understanding that a visit may appear in more than one group, DAWN found, that out of all drug misuse or abuse ED visits,

• 1,173,654 ED visits, or 51.0 percent of drug misuse or abuse ED visits, involved nonmedical use of pharmaceuticals;
• 1,171,024 ED visits, or 50.9 percent, involved illicit drugs; and
• 687,574 ED visits, or 29.9 percent, involved alcohol.

2.2 Trends in ED Visits Involving Drug Misuse or Abuse, 2004–2010

This section presents the trends in the estimates of ED visits involving drug misuse or abuse for the period from 2004 through 2010 (Table 3). Differences between years are presented in terms of the percentage increase or decrease in visits in 2010 compared with the estimates for 2004 (long-term trends) and for 2008 and 2009 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Between 2004 and 2010, the overall number of ED visits attributable to drug misuse or abuse has not increased significantly, though there was a 15 percent increase over the past two years (2008–2010). ED visits related to the use of pharmaceuticals with no other drug involvement rose substantially (132%), as did the use of pharmaceuticals with illicit drugs (139%), pharmaceuticals with alcohol (63%), and pharmaceuticals combined with both illicit drugs and alcohol (94%). The increases reflect over 440,000 more ED visits related to pharmaceuticals alone in 2010 compared with 2004, over 145,000 more ED visits related to pharmaceuticals and illicit drugs, almost 90,000 more ED visits related to pharmaceuticals and alcohol, and over 40,000 more visits related to all three types of substances.

3. ILLICIT DRUGS

3.1 ED Visits Involving Illicit Drugs, 2010

For analysis, DAWN groups together ED visits that involve illicit drugs. These substances include cocaine, heroin, marijuana, synthetic cannabinoids, amphetamines/methamphetamine, MDMA (Ecstasy), GHB (4-hydroxybutanoic acid), flunitrazepam (Rohypnol), ketamine, LSD, PCP, and hallucinogens. Visits involving the inhalation of nonmedical substances for their psychoactive properties (e.g., sniffing model airplane glue) are also included.⁶

Of the approximately 2.3 million drug misuse or abuse ED visits that occurred during 2010, a total of 1,171,024, or just over half, involved illicit drugs (Table 4). A majority (58.8%) of illicit drug ED visits involved multiple drugs. Overall, 28.8 percent of visits involving illicit drugs also involved alcohol.

Cocaine and marijuana were the most commonly involved drugs, with 488,101 ED visits (41.7%) and 461,028 ED visits (39.4%), respectively. Cocaine and marijuana were followed by heroin, at 224,706 ED visits, or 19.2 percent, and then by amphetamines/methamphetamine, at 137,947 visits, or 11.8 percent.⁷

Other illicit drugs involved in ED visits occurred at levels under 5 percent and included the following:

• PCP, in 53,542 visits;
• MDMA (Ecstasy), in 21,836 visits;
• synthetic cannabinoids, in 11,406 visits;
• inhalants, in 11,401 visits;
• hallucinogens (not elsewhere classified), in 6,107 visits;
• LSD, in 3,817 visits;
• GHB, in 1,787 visits;
• ketamine, in 915 visits; and
• flunitrazapam (Rohypnol), in 657 visits.

Synthetic cannabinoids, also known as "Spice" or "K2," appeared for the first time at reportable levels in DAWN in 2010; they were involved in 11,406 ED visits (1.0%). While there appears to be a number of different chemical compositions, synthetic cannabinoids are functionally similar to Δ9-tetrahydrocannabinol (THC), the active ingredient in cannabis.⁸ Users report effects similar to those produced by marijuana, and regular users may experience withdrawal and addiction symptoms.⁹ According to the Monitoring the Future survey, almost one in nine, or 11.4 percent, of high school seniors reported using synthetic cannabinoids in 2011.^10,11

In 2010, there were 378.5 ED visits that involved illicit drugs for each 100,000 persons in the U.S. population (Table 5). The highest rates were found for cocaine involvement (157.8 ED visits per 100,000 population) and marijuana (149.0 visits) (Figure 2). These were followed by heroin (72.6 visits per 100,000 population), amphetamines/methamphetamine (44.6 visits), PCP (17.3 visits), MDMA (Ecstasy) (7.1 visits), inhalants (3.7 visits), and synthetic cannabinoids (3.7 visits). Lower-incidence drugs had rates below 2.0 visits per 100,000 population.

Figure 2
Rates of ED visits per 100,000 population involving illicit drugs, 2010

   D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.

Table 6 presents estimates of the number of ED visits in 2010 involving illicit drugs, by sex, age, and race/ethnicity categories. To facilitate comparisons between demographic groups (e.g., compare males to females), Table 7 and Figure 3 present the rates of ED visits per 100,000 population. For most illicit drugs, the rates were higher for males than for females. The commonly found drugs varied by age: 18- to 20-year-olds had the highest rate of medical emergencies involving marijuana (516.2 visits per 100,000 population aged 18 to 20), 25- to 29-year-olds had the highest rates for heroin (186.9 visits per 100,000 population aged 25 to 29) and amphetamines/methamphetamine (124.3 visits), and 35- to 44-year-olds had the highest rates for cocaine (327.6 visits per 100,000 population aged 35 to 44).

Table 7
Rates of ED visits per 100,000 population involving illicit drugs, by patient demographics, 2010

Patient demographics	All illicits	Cocaine	Heroin	Marijuana	Amphetamines/ methamphet- amine	MDMA (Ecstasy)	GHB	LSD	PCP
(1) The classification of drugs used in DAWN is derived from the Multum Lexicon, © 2011 Lexi-Comp, Inc. and/or Cerner Multum, Inc. The classification was modified to meet DAWN's unique requirements (2010). The Multum Licensing Agreement governing use of the Lexicon can be found on the DAWN Web site at https://www.samhsa.gov/data/dawn/MultumLicenseAgreement.pdf. (2) All rates are ED visits per 100,000 population. Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2010) issued by the U.S. Census Bureau. (3) ED visits often involve multiple drugs. Such visits will appear multiple times in this table (e.g., a visit involving both cocaine and marijuana will appear twice in this table). The sum of visits by drug will be greater than the total, and the sum of percentages by drug will be greater than 100. NOTE: An asterisk (*) indicates that an estimate with a relative standard error greater than 50%, or an estimate based on fewer than 30 visits, has been suppressed. A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations. SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.
Rates of ED visits, illicit drugs (1,2,3)	378.5	157.8	72.6	149.0	44.6	7.1	0.6	1.2	17.3
Sex	—	—	—	—	—	—	—	—	—
Male	503.7	206.0	97.7	199.9	51.1	8.7	0.7	1.8	25.1
Female	257.0	111.0	48.2	99.7	38.2	5.5	0.5	0.7	9.8
Age	—	—	—	—	—	—	—	—	—
0–5 years	2.8	*	*	*	*	*	*	*	*
6–11 years	3.4	*	*	*	*	*	*	*	*
12–17 years	289.4	20.3	12.3	222.5	19.8	25.1	*	4.1	3.9
18–20 years	774.7	114.6	114.1	516.2	80.4	36.6	*	*	*
21–24 years	785.4	193.9	166.8	412.2	103.6	26.2	2.3	1.7	47.8
25–29 years	774.5	253.7	186.9	324.2	124.3	12.5	1.7	1.5	48.2
30–34 years	750.8	299.6	152.4	280.4	118.7	5.8	1.4	0.6	52.7
35–44 years	604.8	327.6	126.2	173.0	75.7	5.0	0.4	*	27.1
45–54 years	491.5	310.5	88.2	117.6	40.5	0.3	0.2	*	12.3
55–64 years	182.3	116.0	39.6	38.1	11.5	*	*	*	2.7
65 years and older	14.1	8.0	3.4	2.9	0.6	*	*	*	*

Figure 3
Rates of ED visits per 100,000 population involving illicit drugs, by selected drugs, age, and sex, 2010

   D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.

Considering race/ethnicity, 50.1 percent of patients were White, 30.4 percent were Black, 11.6 percent were Hispanic, 1.1 percent were of other or multiple race/ethnic groups, and 6.8 percent were of unknown race/ethnicity. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

Overall, 40.9 percent of visits involving illicit drugs resulted in some form of follow-up, including admission to the hospital (23.9%), transfer to another health care facility (10.8%), or referral to a drug detox/dependency program (6.3%) (Table 8). Most other patients (48.1%) were treated and released to home, with the remainder (11.0%) experiencing other outcomes.

3.2 Trends in ED Visits Involving Illicit Drugs, 2004–2010

This section presents the trends in the estimates of ED visits involving illicit drugs for the period from 2004 through 2010 (Table 9). Differences between years are presented in terms of the percentage increase or decrease in visits in 2009 compared with the estimates for 2004 (long-term trends) and for 2008 and 2009 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

The overall level of ED visits involving illicit drugs was stable between 2004 and 2008. From 2008 to 2010, though, there was a significant uptick (18% increase). Marijuana involvement has seen a steady increase between 2004 and 2009, with a notable uptick (22% increase) between 2009 and 2010. This rise echoes the increase in the rate of marijuana use between 2007 and 2010 found by the 2010 National Survey of Drug Use and Health (NSDUH) (5.8% to 6.9%).¹²

Amphetamines/methamphetamine involvement declined between 2004 and 2009 but saw a 47 percent increase between 2009 and 2010 that returned this usage to its 2005 level. Looked at separately, however, the ratio of amphetamines-involved visits to methamphetamine-involved visits is quite different between 2004 and 2010. In 2004, there were almost four methamphetamine-involved visits for every amphetamines-related visit; in 2010, there were fewer than two. MDMA (Ecstasy) involvement also increased gradually between 2004 and 2009 but appeared to stabilize between 2009 and 2010.

4. ALCOHOL

4.1 ED Visits Involving Drugs and Alcohol Taken Together, 2010

According to the National Institute on Alcohol Abuse and Alcoholism (NIAAA), more than 150 medications have harmful additive or interactive effects when combined with alcohol. The harmful effects of combining drugs with alcohol are heightened by drugs that depress the central nervous system, such as heroin, opiate pain relievers, benzodiazepines (anti-anxiety drugs), antihistamines, and antidepressants. These drug-alcohol interactions may result in increased risk of illness, injury, and even death. Medications for certain disorders—including diabetes, high blood pressure, and heart disease—also can have harmful interactions with alcohol.¹³

In 2010, over 500,000 ED visits involved drugs combined with alcohol (Table 10). This represents nearly a quarter of all ED visits associated with drug misuse or abuse.

Illicit drugs were involved in over half (59.8%) of ED visits involving alcohol-drug combinations, with cocaine and marijuana representing the greater proportions of such visits (30.2% and 26.7%, respectively) (Table 11). Pharmaceuticals were involved in over half (55.8%) of such visits. Anxiolytics, sedatives, and hypnotics (drugs to treat insomnia and anxiety) were involved in 23.1 percent of visits, with the largest part of that category being benzodiazepines (19.7%). Pain relievers were involved in a similar number of visits (23.0%), with narcotic pain relievers accounting for over half of that number (14.0%). Psychotherapeutic agents (antidepressants and antipsychotics) were involved in 7.9 percent of visits involving alcohol-drug combinations.

Looking at alcohol involvement from the perspective of all visits involving drug misuse or abuse, DAWN found that 28.8 percent of visits involving illicit drugs also involved alcohol (Table 12). Above-average levels of alcohol involvement were found for visits involving ketamine (40.2%), MDMA (Ecstasy) (38.0%), LSD (35.6%), cocaine (35.0%), and marijuana (32.7%). Among visits involving pharmaceuticals, 23.4 percent of visits also involved alcohol. Above-average levels of alcohol involvement were found for visits involving central nervous system stimulants (e.g., ADHD drugs) (37.5%), nonsteroidal anti-inflammatories (32.2%), antidepressants (28.5%), antipsychotics (27.4%), and benzodiazepines (27.2%).

The rate of ED visits involving alcohol was higher for males (240.1 visits) than for females (126.7 visits) (Table 13, Figure 4). By age, the highest rate was found for patients aged 21 to 24 (354.6 visits).

Figure 4
Rates of ED visits per 100,000 population involving alcohol, by age and sex, 2010

   D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.

Considering race/ethnicity, 58.8 percent of patients were White, 22.8 percent were Black, 10.7 percent were Hispanic, 1.3 percent were of other or multiple race/ethnic groups, and 6.4 percent were of unknown race/ethnicity. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

Just under half (46.2%) of patients seen for alcohol-related ED visits received follow-up care: 28.6 percent were admitted to the hospital, 11.7 percent were transferred to another facility, and the balance (5.9%) was referred to detox/treatment (Table 14). The remaining patients were treated and released to home (44.9%) or had other outcomes (10.2%).

4.2 Underage Drinking

The use of alcohol by those under the age of 21 is of substantial concern to substance abuse professionals and public health agencies. Alcohol abuse can have many immediate adverse consequences for youth and also lead to dangerous patterns of alcohol abuse in adulthood. Intervention at an early age is critical to preventing these patterns from developing. Intervention during an ED visit may be an efficient way to identify those youth at higher risk.

In 2010, of the nearly 460,000 drug abuse–related ED visits made by patients aged 20 or younger, almost half (189,060, or 45.2%) involved alcohol (Table 15).

Of these ED visits involving underage drinking, 73,716 visits were made by patients aged 12 to 17, and 114,722 visits were made by patients aged 18 to 20 (Table 16). For both age groups, about two thirds of these visits involved just alcohol, with the remainder involving alcohol taken with other drugs.

The rate of medical emergencies involving use of alcohol was 291.0 visits per 100,000 population aged 12 to 17 and 848.7 per 100,000 population aged 18 to 20, almost a threefold difference. The pattern is similar when looking at ED visits for either alcohol alone or alcohol used in combination with other drugs (Figure 5).

4.3 Trends in ED Visits Involving Alcohol, 2004–2010

This section presents the trends in the estimates of ED visits involving alcohol for the period from 2004 through 2010 (Table 17). Differences between years are presented in terms of the percentage increase or decrease in visits in 2010 compared with the estimates for 2004 (long-term trends) and for 2008 and 2009 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Involvement of alcohol in drug-related medical emergencies has remained stable over the period from 2004 through 2010. Underage drinking has, likewise, remained constant for youth aged 12 to 17 and young adults aged 18 to 20.

5. NONMEDICAL USE OF PHARMACEUTICALS

5.1 ED Visits Involving Nonmedical Use of Pharmaceuticals, 2010

There is growing concern in the public health community about the misuse or abuse of pharmaceuticals. When taken as directed for legitimate medical purposes, pharmaceuticals are usually safe and effective. However, when misused, pharmaceuticals can be just as dangerous and debilitating as illegal drugs.¹⁴ Furthermore, as documented by the 2010 National Survey of Drug Use and Health (NSDUH), misuse of pharmaceuticals appears to be widespread. In 2010, NSDUH estimated that 7.0 million persons aged 12 or older used prescription-type pain relievers, tranquilizers, stimulants, or sedatives nonmedically in the past month. Initiation rates for nonmedical pain reliever use continue to be second only to marijuana rates, with 2 million or more new nonmedical pain reliever users each year since 2002, including over 500,000 who initiate use without ever having used another illicit drug. The number of persons receiving substance use treatment within the past year for misuse of pain relievers more than doubled between 2002 and 2010, from 199,000 to 406,000.¹⁵

DAWN defines nonmedical use to include misuse or abuse of any therapeutic substance. While use of any illicit drug is assumed to constitute drug abuse, nonmedical use of pharmaceuticals must be substantiated in the patient's ED medical records. Evidence supporting nonmedical use includes the following:

• taking more than the prescribed dose of a prescription drug;
• taking more than the recommended dose of an over-the-counter pharmaceutical or supplement;
• taking a drug prescribed for another individual;
• taking a drug obtained illegally or without a legitimate prescription;
• deliberate poisoning with a pharmaceutical by another person; and
• any use of a prescription drug, an over-the-counter pharmaceutical, or a dietary supplement that ED medical staff document in the patient's medical record as misuse or abuse.

Nonmedical use of pharmaceuticals may involve a single pharmaceutical, multiple pharmaceuticals, or pharmaceuticals in combination with illicit drugs or alcohol. Pharmaceuticals that the patient may have taken recently but that are not related to the reason for the ED visit are not included in the DAWN data.¹⁶

For 2010, DAWN estimates that 1,173,654 ED visits involved nonmedical use of prescription medicines, over-the-counter drugs, or other types of pharmaceuticals (Table 18). This represents about a quarter (23.9%) of all drug-related ED visits and over half (51.0%) of ED visits for drug abuse or misuse. Over half (54.7%) of medical emergencies seen in the ED resulting from nonmedical use of pharmaceuticals involved multiple drugs.¹⁷ About one in five (17.4%) of ED visits involving nonmedical use of pharmaceuticals also involved alcohol.

At 48.3 percent, pain relievers were the most common type of drugs involved in medical emergencies associated with nonmedical use of pharmaceuticals, with narcotic pain relievers accounting for 30.7 percent. Specific narcotic pain relievers seen more commonly were oxycodone, hydrocodone, and methadone at 12.5, 8.2, and 5.6 percent, respectively.¹⁸ Non-narcotic pain relievers—such as acetaminophen, nonsteroidal anti-inflammatories (e.g., ibuprofen, naproxen), and aspirin—were seen at lower levels of between 1 and 4 percent.

Anxiolytics, sedatives, and hypnotics (drugs to treat anxiety and insomnia) were found in 34.0 percent of visits related to nonmedical use of pharmaceuticals. Benzodiazepines (anti-anxiety drugs) were involved in 29.5 percent of ED visits, with alprazolam (e.g., Xanax) indicated in about a third (10.6%) of such visits.

Among other major categories of drugs, psychotherapeutic agents (antidepressants and antipsychotics) were involved in 11.2 percent of ED visits related to nonmedical use of pharmaceuticals. Respiratory agents, cardiovascular agents, muscle relaxants, and anticonvulsants each were involved in about 3 to 5 percent of ED visits.

When population size and sampling error are taken into account, visits for nonmedical use of pharmaceuticals did not differ between males and females (374.2 and 383.9 visits per 100,000 population, respectively; Table 19, Figure 6). The rate of ED visits for patients in age categories between 21 and 34 were all over 600 visits per 100,000 population, with lower levels observed for younger and older patients.

Figure 6
Rates of ED visits per 100,000 population involving nonmedical use of pharmaceuticals, by age and sex, 2010

   D

SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.

In terms of race and ethnicity, 71.3 percent of visits related to nonmedical use of pharmaceuticals involved patients who were White, 12.6 percent were Black, and 8.4 percent were Hispanic. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

Some form of follow-up was observed for 37.4 percent of patients whose visits involved nonmedical use of pharmaceuticals (Table 20). Follow-up included admission to the hospital (25.5%), transfer to another facility (9.5%), and referral to detox/treatment (2.4%). Of the remainder, 54.0 percent of patients were treated and released to home, and 8.6 percent had other outcomes. This distribution of outcomes is similar to that found for patients whose ED visits involved illicit drugs (see Table 8).

5.2 Trends in ED Visits Involving Nonmedical Use of Pharmaceuticals, 2004–2010

This section presents the trends in the estimates of ED visits involving nonmedical use of pharmaceuticals for the period from 2004 through 2010 (Table 21). Differences between years are presented in terms of the percentage increase or decrease in visits in 2010 compared with the estimates for 2004 (long-term trends) and for 2008 and 2009 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

Large increases in the number of ED visits involving nonmedical use of pharmaceuticals were observed between 2004 and 2010. It is likely that there are multiple causes contributing to these increases. Some portion may be associated with the greater number of prescriptions being written, making prescription drugs more accessible and able to be diverted. Also, as more people are taking prescription medications as part of their regular health care, there is more risk that drugs taken as prescribed will interact with other drugs that are being used nonmedically. It is beyond the scope of this report to explore the causes behind the growing numbers of ED visits involving misuse or abuse of pharmaceuticals, and further research is needed.

Medical emergencies related to nonmedical use of pharmaceuticals increased 119 percent in the period from 2004 to 2010, rising from about a half million visits (535,449 visits) to over one million visits (1,173,654 visits). Contributing to this rise were significant long-term increases in the number of visits involving narcotic pain relievers, which increased 149 percent, or 215,271 visits, beyond its 2004 level of 144,650 visits. ED visits for narcotic pain relievers that more than doubled during this period were fentanyl, hydrocodone, hydromorphone, morphine, and oxycodone. Visits involving tramadol (e.g., Ultram), a narcotic-like opiate agonist used for moderate to severe pain, increased 235 percent, reaching 16,251 visits in 2010.

Between 2004 and 2010, the number of visits involving drugs for anxiety and insomnia increased 125 percent overall—a jump of more than 221,000 visits over the 2004 level of 177,394 visits. Benzodiazepines (e.g., alprazolam, clonazepam, diazepam, lorazepam) have shown a regular upward trend, with 202,145 more visits in 2010 than in 2004. Visits involving zolpidem (e.g., Ambien), a sleeping aid with benzodiazepine-like properties, increased 150 percent, reaching 31,994 visits in 2010. Muscle relaxants (e.g., carisprodol, cyclobenzaprine) increased 107 percent, reaching 53,708 visits in 2010. One of the drugs used to treat attention deficit hyperactivity disorder (ADHD), amphetamine-dextroamphetamine (e.g., Adderall), saw a 392 percent increase between 2004 and 2010 for a total of 11,327 visits in 2010.

A 59 percent increase was seen for visits involving cardiovascular agents for a total of 43,698 visits in 2010. While part of the increase in visits involving cardiovascular agents may signal an increase in their misuse, part may be due to the interaction of cardiovascular agents taken as prescribed with other drugs and therapeutic substances used medically and nonmedically.

6. DRUG-RELATED SUICIDE ATTEMPTS

6.1 ED Visits Involving Drug-Related Suicide Attempts, 2010

In 2008, more than 36,000 suicides occurred in the United States, and suicide was the second leading cause of death for adults aged 25 to 34.¹⁹ This is the equivalent of 1 suicide every 15 minutes, or 11.6 suicides per 100,000 population. Substance abuse is strongly associated with suicide attempts. Evidence suggests that one third of those who died by suicide were positive for alcohol at the time of death and that nearly one in five had evidence of opiates.²⁰ Highlighting the relevance of drugs to the overall problem of life-threatening suicide attempts, the Centers for Disease Control and Prevention's National Electronic Injury Surveillance System estimated that overall there were about 325,000 ED visits in 2008 for suicide attempts by all methods by patients aged 18 or older that resulted in ED visits; for the same year and age range, DAWN estimated there were about 175,000 ED visits for suicide attempts involving drugs.

DAWN data provide a unique window to study life-threatening suicide attempts that involve drugs in respect to the types of drugs involved, the characteristics of the patients, and the follow-up treatments provided. DAWN reports on suicide attempts involving all types of illicit drugs and prescription drugs as well as over-the-counter products and attempts involving alcohol alone for patients aged 20 or younger. DAWN cases are not limited to drug overdoses. Suicide attempts involving firearms, for example, are included as DAWN cases if drugs are noted as being involved at the time of the suicide attempt.²¹

DAWN estimated there were 212,736 ED visits resulting from drug-related suicide attempts in 2010 (Table 22). Almost all (94.7%) involved a prescription drug or over-the-counter medication, about two thirds (62.6%) involved multiple drugs, and about one quarter (25.3%) involved alcohol.

About a fifth (17.6%) involved illicit drugs. Marijuana and cocaine were the more commonly involved illicit drugs, appearing in 8.1 and 7.4 percent of visits, respectively.

Pharmaceuticals were much more common than illicit drugs in suicide attempts:

• Pain relievers were found to be involved in 37.1 percent of drug-related suicide attempts. Narcotic pain relievers accounted for almost half that number (15.5%), and acetaminophen products accounted for about a third (13.5%).
• Benzodiazepines (anti-anxiety drugs) were found to be involved in 28.4 percent of drug-related suicide attempts. Alprazolam (e.g., Xanax) and clonazepam (e.g., Klonopin) each accounted about a third (10.6% and 9.4%, respectively).
• Antidepressants appeared in 19.9 percent of visits. About half (10.5%) of those visits involved SSRI antidepressants such as sertraline (e.g., Zoloft), fluoxetine (e.g., Prozac), and citalopram (e.g., Celexa). Trazodone (e.g., Desyrel^®) accounted for about a quarter (5.1%).
• Antipsychotics, as a whole, appeared in 13.5 percent of visits. At 11.0 percent, the newer types of atypical antipsychotics accounted for most of those visits. Quetiapine (e.g., Seroquel^®) was the most common atypical antipsychotic (6.5%).

After population size and sampling error are taken into account, the rate of drug-related suicide-attempt visits for females (80.8 visits per 100,000 population) was higher than that for males (56.3 visits per 100,000) (Table 23, Figure 7). In respect to age, rates ranged from 13.4 visits per 100,000 population for those aged 65 or older to 160.1 visits for those aged 18 to 20.

Figure 7
Rates of ED visits per 100,000 population involving drug-related suicide attempts, by age and sex, 2010

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SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.

Considering race/ethnicity, 63.6 percent of the suicide attempts involved patients who were White, 15.8 percent were Black, 11.1 percent were Hispanic, 2.6 percent were of other or multiple race/ethnic groups, and 6.9 percent were of unknown race/ethnicity. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing from ED records.

Overall, 77.8 percent of patients attempting drug-related suicide had some form of follow-up. About half (49.9%) were admitted for inpatient hospital care (17.9% were admitted to an intensive or critical care unit [ICU], 12.7% went to a psychiatric unit, and 19.1% went to other units); a quarter (24.8%) were transferred to another health care facility; and 3.0 percent were discharged with a referral to detox/treatment (Table 24). The remainder of patients were either treated and discharged to home (16.0%) or had other outcomes (6.2%).

DAWN only records death as the outcome if the patient died in the ED after admission. DAWN does not record deaths for patients who died prior to admission to the ED or after admission to inpatient units of the hospital or transfer to another facility. Therefore, death as an ED disposition is rarely observed by DAWN.

6.2 Trends in ED Visits Involving Drug-Related Suicide Attempts, 2004–2010

This section presents the trends in the estimates of drug-related ED visits involving suicide attempts for the period from 2004 through 2010. Differences between years are presented in terms of the percentage increase or decrease in visits in 2010 compared with the estimates for 2004 (long-term trends) and for 2008 and 2009 (short-term trends). Only statistically significant changes are discussed and displayed in the tables.

With 212,736 visits in 2010, the number of drug-related suicide attempts has been stable from 2004 to 2010 (Table 25). There have been changes, however, in the types of drugs involved. A 95 percent rise in involvement of narcotic pain relievers occurred between 2004 and 2010. Hydrocodone (e.g., Vicodin) and oxycodone (e.g., OxyContin) increased 83 percent and 147 percent, respectively.

A large rise (53%) was also observed between 2004 and 2010 for drugs used to treat anxiety and insomnia. Benzodiazepine involvement in general rose 63 percent, with large increases observed for each of the following drugs: alprazolam (e.g., Xanax), clonazepam (e.g., Klonopin), lorazepam (e.g., Ativan), and zolpidem (e.g., Ambien).

7. SEEKING DETOX SERVICES

7.1 ED Visits Involving Seeking Detox Services, 2010

The category of visits referred to as "seeking detox" includes nonemergency requests for admission for detoxification and visits to obtain medical clearance before entry to a detox program as well as acute emergencies in which an individual is experiencing withdrawal symptoms and seeking detox.²² Because detox may be sought through other avenues (e.g., direct admission to a hospital, services provided through private clinics, entry into programs outside the community), the overall demand for detox services is most likely higher than suggested by DAWN estimates.

DAWN estimates that there were 232,542 drug-related ED visits for patients seeking detox or substance abuse treatment services during 2009 (Table 26). Visits for almost three quarters (67.8%) of patients seeking detox involved multiple drugs. On average, 29.8 percent of visits associated with seeking detox involved alcohol.²³ Cocaine was observed in 27.6 percent of visits, heroin in 26.7 percent, marijuana in 18.5 percent, and amphetamines/methamphetamine in 5.9 percent. Other illicit drugs were seen at lower levels. Among pharmaceuticals, narcotic pain relievers were observed in 45.4 percent of visits, including oxycodone at 28.8 percent. Benzodiazepines (anti-anxiety drugs) were observed in 23.1 percent of visits, with alprazolam (e.g., Xanax) at 12.2 percent and clonazepam (e.g., Klonopin) at 2.8 percent.

When population size and sampling error are taken into account, the rate of seeking detox visits for males (99.2 per 100,000 population) was higher than that for females (51.9 per 100,000 population) (Table 27, Figure 8). Rates of seeking detox visits were over 100 visits per 100,000 population for those aged 18 to 44, peaking at 206.7 for those aged 21 to 24.

Figure 8
Rates of ED visits per 100,000 population involving seeking detox services, by age and sex, 2010

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SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.

In terms of race/ethnicity, the majority (76.8%) of seeking detox visits involved patients who were White, and 14.3 percent were Black. DAWN does not produce population-based rates for race/ethnicity categories because race/ethnicity information is often missing in ED records.

Nearly 60 percent (58.1%) of ED patients classified as seeking detox obtained some follow-up: 32.2 percent were admitted to the hospital, 17.3 percent were referred to detox/treatment services, and 8.6 percent were transferred to another facility (Table 28). The plurality of those admitted to the hospital were sent to the chemical dependency/detox unit. The remaining patients were treated and discharged home (31.1%) or had other outcomes.

7.2 Trends in ED Visits Involving Seeking Detox Services, 2004–2010

This section presents the trends in the estimates of ED visits involving seeking detox services for the period from 2004 through 2010 (Table 29). Differences between years are presented in terms of the percentage increase or decrease in visits in 2010 compared with the estimates for 2004 (long-term trends) and for 2008 and 2009 (short-term trends). Only statistically significant changes are discussed and displayed in the table.

While ED visits by patients seeking detox for illicit drugs did not change significantly either in the long term or short term, a short-term increase of 22 percent between 2009 and 2010 was observed for pharmaceutical involvement. A major contributor to the increase were pain relievers, which saw a 34 percent increase; specifically, oxycodone-related ED visits increased 47 percent between 2009 and 2010.

8. ADVERSE REACTIONS TO PHARMACEUTICALS

8.1 ED Visits Involving Adverse Reactions to Pharmaceuticals, 2010

Adverse reactions to pharmaceuticals are a growing problem in the United States. It is likely that there are multiple causes contributing to increases in adverse reactions. Some portion may be associated with the greater number of prescriptions being written and more people taking prescription drugs as part of their medical care. Additionally, people of all ages are increasingly being prescribed multiple drugs simultaneously, which, in turn, increases the possibility for unintended interactions. This is particularly common among older populations who are placed on long-term medication for chronic conditions, and the number of older persons in the nation is growing.²⁴ While it is beyond the scope of this report to assess the precise impact of these different causes, DAWN data provide insight concerning the number and characteristics of medical emergencies resulting from the recent use of prescription drugs, over-the-counter pharmaceuticals, or other therapeutic substances used as prescribed or indicated. Included in DAWN are ED visits related to side effects, drug-drug interactions, and drug-alcohol interactions. Visits involving illicit drug abuse, alcohol abuse, or documented misuse of pharmaceuticals are excluded from this grouping.²⁵

As with all ED visits that DAWN considers to be drug related, the involvement of a drug must be documented in the ED records. If the relationship between a drug and an adverse reaction is not recognized, a visit will not be considered drug related and will not be captured by DAWN. Also, adverse reactions that are identified in different medical settings (e.g., during a visit to the doctor's office or while a patient is already hospitalized) will not be captured by DAWN. Therefore, the total number of people experiencing adverse drug reactions is greater than reported by DAWN.

For 2010, DAWN estimates that 2,329,221 ED visits (Table 30), or 752.8 visits per 100,000 population (Table 31), involved adverse reactions to prescription medicines, over-the-counter drugs, or other types of pharmaceuticals. This represents just under half (47.4%) of all drug-related ED visits. About one in five (18.8%) involved multiple drugs. Alcohol was a contributing factor in just 1.3 percent of adverse reaction visits.

Table 31
ED visits and rates involving adverse reaction to pharmaceuticals, by patient demographics, 2010

Patient demographics	ED visits	Percent of ED visits	Rate of ED visits per 100,000 population (1)
(1) All rates are ED visits per 100,000 population. Population estimates are drawn from the set of United States Resident Population Estimates by Age, Sex, Race, and Hispanic Origin (Vintage 2010) issued by the U.S. Census Bureau. (2) Estimates of ED visits are based on a representative sample of general, non-Federal, short-stay hospitals in the United States with 24-hour EDs. NOTE: A dash (—) indicates a blank cell. Rates are not provided for race and ethnicity subgroups because of data limitations. SOURCE: Center for Behavioral Health Statistics and Quality, SAMHSA, Drug Abuse Warning Network, 2010.
Total ED visits, adverse reaction (2)	2,329,221	100.0	752.8
Sex	—	—	—
Male	897,914	38.5	590.2
Female	1,430,179	61.4	909.3
Unknown	1,128	0.0	—
Age	—	—	—
0–5 years	179,262	7.7	736.0
6–11 years	56,946	2.4	231.8
12–17 years	70,527	3.0	278.5
18–20 years	74,424	3.2	550.6
21–24 years	106,721	4.6	621.2
25–29 years	134,864	5.8	638.3
30–34 years	129,791	5.6	646.3
35–44 years	269,650	11.6	658.6
45–54 years	323,798	13.9	719.0
55–64 years	303,503	13.0	824.6
65 years and older	679,160	29.2	1,678.9
Unknown	575	0.0	—
Race/ethnicity	—	—	—
White	1,525,370	65.5	—
Black	327,749	14.1	—
Hispanic	236,752	10.2	—
Other or two or more race/ethnicities	63,793	2.7	—
Unknown	175,558	7.5	—