The DAWN Report: Emergency Department Visits Involving Phencyclidine (PCP)

In Brief
  • Overall, the estimated number of phencyclidine (PCP)-related emergency department (ED) visits increased more than 400 percent between 2005 and 2011 (from 14,825 to 75,538 visits); more recently, the number of these visits doubled between 2009 and 2011 (from 36,719 to 75,538)
  • The largest increase in PCP-related ED visits was seen among patients aged 25 to 34, an increase of more than 500 percent from 2005 to 2011 (from 5,556 to 34,329 visits)
  • In 2011, about two thirds (69 percent) of PCP-related ED visits were made by males, and nearly half (45 percent) were made by persons aged 25 to 34
  • Other illicit drugs, such as marijuana, cocaine, and heroin, were involved in approximately half (48 percent) of PCP-related ED visits in 2011

Phencyclidine, commonly known as PCP or "angel dust," is sold illegally in many forms, including powder, crystal, tablet, capsule, and liquid.1 Most often, it is smoked in combination with marijuana or tobacco.1 According to the Drug Enforcement Administration (DEA), the popularity of PCP use has fluctuated since it first emerged as a drug of abuse in the late 1960s: "PCP abuse subsequently waned throughout the 1970s until the early 1980s, when abuse rose again…. It is believed that the widespread abuse and availability of crack cocaine in the late 1980s and early 1990s reduced the demand for PCP."1 DEA also noted that the resurgence of PCP in the 1980s was mostly among teenagers and localized in certain metropolitan areas—Baltimore, Chicago, Detroit, Los Angeles, New Orleans, New York City, San Diego, San Francisco, St. Louis, and Washington, DC.1 Recent Drug Abuse Warning Network (DAWN) estimates for a selection of metropolitan areas indicate that there continues to be geographic variation, with the number of PCP-related emergency department (ED) visits increasing in some areas (New York City, Chicago) and remaining stable in others (Seattle, San Francisco, and Phoenix); estimates in remaining areas were too small or imprecise to report consistently.2

PCP is known to cause hallucinations similar to MDMA (3,4-methylenedioxy-N-methylamphetamine, also known as Ecstasy) and LSD (lysergic acid diethylamide), but unlike those drugs, PCP can lead to hostile behavior that may result in episodes of extreme violence.3 PCP users often feel detached or distant from their environment and can experience distorted sights and sounds.4 Severe symptoms of PCP use can include irregular breathing, seizures, and coma.3 Furthermore, users can become addicted to PCP and experience anxiety and suicidal ideation.1 Individuals experiencing negative health effects after using PCP may seek treatment or be brought by law enforcement to the ED for immediate care.

ED visits associated with PCP use are tracked through DAWN—a public health surveillance system that monitors drug-related ED visits in the United States. To be a DAWN case, the ED visit must have involved a drug, either as the direct cause of the visit or as a contributing factor. Drug involvement must be documented in the ED record, but DAWN does not require that all reported drugs be confirmed by laboratory testing. Data are collected on numerous illicit drugs, including cocaine, marijuana, heroin, and stimulants (e.g., amphetamines and methamphetamines) as well as pharmaceutical products, such as prescribed and over-the-counter medications. Data are also collected for visits involving alcohol combined with other drugs. For patients aged 20 or younger, data are collected on alcohol when it is the only substance involved in the visit. This issue of The DAWN Report examines recent trends in PCP-related ED visits and highlights characteristics of such visits in 2011.


Trends in PCP-Related ED Visits

Overall, the estimated number of PCP-related ED visits increased more than 400 percent between 2005 and 2011 (from 14,825 to 75,538 visits); more recently, the number of these visits doubled between 2009 and 2011 (from 36,719 to 75,538; Figure 1). In comparison, ED visits involving other hallucinogens—specifically MDMA (Ecstasy) and LSD—increased to a lesser extent between 2005 and 2011. MDMA-related ED visits increased 100 percent (from 11,287 to 22,498 visits), and LSD-related ED visits increased 141 percent (from 2,001 to 4,819 visits).

Figure 1. Emergency Department (ED) Visits Involving Phencyclidine (PCP), MDMA (Ecstasy), and LSD, by Year: 2005 to 2011
This is a line graph comparing emergency department (ED) visits involving phencyclidine (PCP), MDMA (ecstasy), and LSD, by year: 2005 to 2011. Accessible table located below this figure.

Figure 1 Table. Emergency Department (ED) Visits Involving Phencyclidine (PCP), MDMA (Ecstasy), and LSD, by Year: 2005 to 2011
Drug 2005 2006 2007 2008 2009 2010 2011
PCP* 14,825 21,960 28,173 37,266 36,719 53,542 75,538
MDMA (Ecstasy)** 11,287 16,784 12,751 17,888 22,847 21,836 22,498
LSD***   2,001   4,002   3,561   3,287   4,028   3,817   4,819
* The number of visits involving PCP in 2005, 2006, 2007, 2008, 2009, and 2010 is significantly different from 2011 at the .05 level.
** The number of visits involving MDMA (Ecstasy) in 2005 and 2007 is significantly different from 2011 at the .05 level.
*** The number of visits involving LSD in 2005 is significantly different from 2011 at the .05 level.
Source: 2005 to 2011 SAMHSA Drug Abuse Warning Network (DAWN).

Increases in PCP-related ED visits were seen among people of both genders. The sharpest increase occurred between 2009 and 2011, with ED visits by males nearly doubling and visits by females more than doubling. Between 2005 and 2011, PCP-related ED visits by males increased nearly fivefold (from 10,721 to 51,906 visits), and visits by females increased nearly sixfold (from 4,007 to 23,598 visits; Figure 2).

Figure 2. Emergency Department (ED) Visits Involving Phencyclidine (PCP), by Gender and Year: 2005 to 2011
This is a line graph comparing emergency department (ED) visits involving phencyclidine (PCP), by gender and year: 2005 to 2011. Accessible table located below this figure.

Figure 2 Table. Emergency Department (ED) Visits Involving Phencyclidine (PCP), by Gender and Year: 2005 to 2011
Gender 2005 2006 2007 2008 2009 2010 2011
Total* 14,825 21,960 28,173 37,266 36,719 53,542 75,538
Male* 10,721 15,298 20,667 24,020 26,686 38,111 51,906
Female*   4,007   6,661   7,507 13,246 10,032 15,431 23,598
* The difference between 2005 and 2011 is statistically significant at the .05 level.
Source: 2005 to 2011 SAMHSA Drug Abuse Warning Network (DAWN).

Increases were also observed for young adults. The largest increase by age group was seen among patients aged 25 to 34; in this age group, the number of PCP-related visits increased 518 percent (from 5,556 visits to 34,329) (Table 1). Also, visits by adults aged 18 to 24 increased 289 percent (from 3,643 visits to 14,175). There were no statistically significant increases for the other age groups.

Table 1. Emergency Department (ED) Visits Involving Phencyclidine (PCP), by Age* and Year: 2005 vs. 2011
Age Group Number of
ED Visits,
2005
Number of
ED Visits,
2011
Percent
Change, 2005
to 2011
Total ED Visits 14,825 75,538 410%
Aged 12 to 17      691   1,965 184%
Aged 18 to 24**   3,643 14,175 289%
Aged 25 to 34**   5,556 34,329 518%
Aged 35 to 44   3,651 14,606 300%
Aged 45 or Older        ***        ***      ***
* ED visits for which age is unknown have been excluded.
** The difference between 2005 and 2011 is statistically significant at the .05 level.
*** Low precision; no estimate reported.
Source: 2005 to 2011 SAMHSA Drug Abuse Warning Network (DAWN).

Increases in PCP-related visits involving young adults were also observed for male patients aged 18 to 24 and 25 to 34. For females, the increase only occurred among patients aged 25 to 34, although it was substantial (from 1,189 visits in 2005 to 12,570 in 2011) (Figure 3). Because of low statistical precision, trends for males and females in other age groups could not be evaluated.

Figure 3. Emergency Department (ED) Visits Involving Phencyclidine (PCP), by Gender, Age Group*, and Year: 2005 vs. 2011
This is a bar graph comparing emergency department (ED) visits involving phencyclidine (PCP), by gender, age group*, and year: 2005 vs. 2011. Accessible table located below this figure.

Figure 3 Table. Emergency Department (ED) Visits Involving Phencyclidine (PCP), by Gender, Age Group*, and Year: 2005 vs. 2011
Year Males
Aged
18 to 24**
Females
Aged
18 to 24
Males
Aged
25 to 34**
Females
Aged
25 to 34**
2005   2,244 1,398   4,270   1,189
2011 10,254 3,921 21,759 12,570
* ED visits for which age and gender are unknown have been excluded.
** The difference between 2005 and 2011 is statistically significant at the .05 level.
Source: 2005 to 2011 SAMHSA Drug Abuse Warning Network (DAWN).

PCP-Related ED Visits in 2011

In 2011, about two thirds (69 percent) of the 75,538 ED visits involving PCP were made by males. Visits made by patients aged 25 to 34 accounted for nearly half (45 percent) of PCP-related ED visits; visits made by those aged 18 to 24 and those aged 35 to 44 each accounted for 19 percent of visits.

Approximately 7 out of 10 (72 percent) PCP-related visits involved other drugs combined with PCP (Figure 4). PCP was combined with one other substance in 37 percent of visits, with two other substances in 18 percent of visits, and with three or more other substances in 18 percent of visits. About one quarter of the PCP-related visits in 2011 involved PCP only (28 percent).

Figure 4. Number of Substances in Emergency Department (ED) Visits Involving Phencyclidine (PCP): 2011
This is a pie graph comparing number of substances in emergency department (ED) visits involving phencyclidine (PCP): 2011. Accessible table located below this figure.

Figure 4 Table. Number of Substances in Emergency Department (ED) Visits Involving Phencyclidine (PCP): 2011
Number of Substances Percentage
PCP Only 28%
PCP and 1 Substance 37%
PCP and 2 Substances 18%
PCP and 3 or More Substances 18%
Note: Percentages may not sum to 100 due to rounding.
Source: 2011 SAMHSA Drug Abuse Warning Network (DAWN).

About half of the PCP-related visits in 2011 involved PCP combined with other illicit drugs (48 percent); one third involved marijuana (32 percent), and one fifth involved cocaine (20 percent) (Table 2). About 27 percent involved PCP and pharmaceuticals such as pain relievers (16 percent) and anti-anxiety and insomnia medications (13 percent). These pharmaceuticals, which have a sedative effect on the body, can interact dangerously with PCP.5

Table 2. Selected Drug Combinations among Emergency Department (ED) Visits Involving Phencyclidine (PCP): 2011
Age Group Number of
ED Visits
Percentage
of Visits*
Total ED Visits 75,538 100%
In Combination with Alcohol         **      **
In Combination with Other Illicit Drugs 36,053   48%
Marijuana 23,965   32%
Cocaine 14,964   20%
Heroin   3,795     5%
In Combination with Pharmaceuticals 20,486   27%
Pain Relievers 12,089   16%
Narcotic Pain Relievers***   4,038     5%
Anti-anxiety and Insomnia Medications   9,806   13%
Benzodiazepines   9,530   13%
* Because multiple drugs may be involved in each visit, estimates of visits by drug may add to more than the total, and percentages may add to more than 100 percent.
** Low precision; no estimate reported
*** Narcotic pain relievers include common brand names such as Vicodin®, Percocet®, OxyContin®, and Darvon®.
Source: 2011 SAMHSA Drug Abuse Warning Network (DAWN).

Discussion

The recent increase in ED visits involving PCP is of particular concern because within the class of illicit drugs that cause hallucinations, PCP is reputed to be the most dangerous and is especially known for causing violent behavior.1 Although PCP may have once been recognized in the general population as a dangerous drug, potential users today may be less likely to know of these risks because of "generational forgetting."6 Findings from the National Forensic Laboratory Information System (NFLIS), which collects data from Federal, State, and local forensic laboratories, support the DAWN finding that PCP abuse is reemerging. In 2011, PCP was ranked 19th on the NFLIS list of the 25 most frequently reported drugs, with an estimated 6,151 total reports.7 Although DAWN is not capable of producing valid regional estimates, metropolitan area estimates suggest that the distribution of ED visits involving PCP and patterns of PCP use are not geographically uniform.2

Based on the DAWN findings, prevention efforts could include warnings about the use of PCP and additional efforts to target adults aged 25 to 34. Increased efficiency might result from geographic targeting of prevention and treatment efforts based on additional studies. Describing common drug combinations with PCP in prevention campaigns may also help to raise awareness that tobacco or marijuana can be laced with PCP; DAWN data show that one third of PCP-related ED visits in 2011 involved marijuana.

By recognizing the signs and symptoms of PCP intoxication, health care providers—especially those on the front lines of emergency care—can help to ensure that patients who come into medical facilities receive immediate and appropriate care. For ED personnel in metropolitan areas with high rates of illicit drug use, heightened awareness of the reemergence of PCP may be especially useful for assessing patients who present with violent or suicidal behavior.


End Notes
1 U.S. Department of Justice, Drug Enforcement Administration. (2003). PCP: The threat remains. Microgram Bulletin, 36(8), 181-190.
2 Substance Abuse and Mental Health Services Administration. (2013). DAWN 2011 emergency department Excel files—Metro tables. Retrieved from http://www.samhsa.gov/data/DAWN.aspx#DAWN 2011 ED Excel Files – Metro Tables
3 Bey, T., & Patel, A. (2007). Phencyclidine intoxication and adverse effects: A clinical and pharmacological review of an illicit drug. California Journal of Emergency Medicine, 8(1), 9-14.
4 National Institute on Drug Abuse. (2009, June). DrugFacts: Hallucinogens—LSD, peyote, psilocybin, and PCP. Retrieved from http://www.drugabuse.gov/publications/drugfacts/hallucinogens-lsd-peyote-psilocybin-pcp
5 The Partnership at Drugfree.org. (2013). Drug guide: PCP. Retrieved from http://www.drugfree.org/drug-guide/pcp
6 Johnston, L. D., O'Malley, P. M., Bachman, J. G., & Schulenberg, J. E. (2011). Monitoring the Future national results on adolescent drug use: Overview of key findings, 2010. Retrieved from http://monitoringthefuture.org/pubs/monographs/mtf-overview2010.pdf
7 U.S. Department of Justice, Drug Enforcement Administration, Office of Diversion Control. (2012, September). National Forensic Laboratory Information System: 2011 annual NFLIS report. Retrieved from http://www.deadiversion.usdoj.gov/nflis/2011annual_rpt.pdf


Suggested Citation
Substance Abuse and Mental Health Services Administration, Center for Behavioral Health Statistics and Quality. (November 12, 2013). The DAWN Report: Emergency Department Visits Involving Phencyclidine (PCP). Rockville, MD.

The Substance Abuse and Mental Health Services Administration (SAMHSA) is the agency within the U.S. Department of Health and Human Services that leads public health efforts to advance the behavioral health of the nation. SAMHSA's mission is to reduce the impact of substance abuse and mental illness on America's communities.

The Drug Abuse Warning Network (DAWN) is a public health surveillance system that monitors drug-related morbidity and mortality. DAWN uses a probability sample of hospitals to produce estimates of drug-related emergency department (ED) visits for the United States and selected metropolitan areas annually. DAWN also produces annual profiles of drug-related deaths reviewed by medical examiners or coroners in selected metropolitan areas and States.

Any ED visit related to recent drug use is included in DAWN. All types of drugs—licit and illicit—are covered. Alcohol involvement is documented for patients of all ages if it occurs with another drug. Alcohol is considered an illicit drug for minors and is documented even if no other drug is involved. The classification of drugs used in DAWN is derived from the Multum Lexicon, copyright 2012 Lexi-Comp, Inc., and/or Cerner Multum, Inc. The Multum Licensing Agreement governing use of the Lexicon can be found at http://www.samhsa.gov/data/DAWN.aspx.

DAWN is one of three major surveys conducted by SAMHSA's Center for Behavioral Health Statistics and Quality (CBHSQ). For more information on other CBHSQ surveys, go to http://www.samhsa.gov/data/. SAMHSA has contracts with Westat (Rockville, MD) and RTI International (Research Triangle Park, NC) to operate the DAWN system and produce publications.

For publications and additional information about DAWN, go to http://www.samhsa.gov/data/DAWN.aspx.

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