Phencyclidine Toxicity

Updated: Mar 28, 2022
  • Author: Patrick L West, MD; Chief Editor: Michael A Miller, MD  more...
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Practice Essentials

Phencyclidine (PCP) is a hallucinogen—specifically, a dissociative anesthetic—that can produce a wide variety of physical and behavioral effects and has a high potential for abuse and dependence. Acute toxicity often resembles a psychotic episode. PCP is often taken in conjunction with other co-ingestants, including ethanol and marijuana. 

PCP is a white crystalline powder that is available in tablet or powder forms, or dissolved in a liquid. It can be snorted, ingested orally, or injected intravenously. It also can be smoked as a "joint" or "wet" ("embalming fluid") when sprinkled on cigarettes or applied to mint or marijuana leaves. [1]  

Newer designer versions such as 3-methoxyphencyclidine (3-MeO-PCP) and 4-MeO PCP now exist. [2]  3-MeO-PCP bonds more strongly to N-methyl-D-aspartate (NMDA) receptors than PCP or 4-MeO-PCP.  However, 4-MeO-PCP is toxic at lower concentrations than either PCP or 3-MeO-PCP. [3, 4]



Phencyclidine (PCP) was originally developed in the 1950s for use as a general anesthetic for surgery, under the trade name Sernyl. Its use was discontinued in humans in 1965 because it often produced postanesthetic delirium with psychotic features, dysphoria, and occasionally extreme agitation. PCP under the name Sernylan was used as a veterinary anesthetic until 1978, after which time it became illegal to use altogether.

In the 1960s, people began illegally manufacturing PCP in laboratories, and by the late 1970s it became a popular street drug. Common street names include the following:

  • Angel dust
  • Peace pill
  • Crystal joint
  • Hog
  • Rocket fuel
  • KJ
  • Elephant tranquilizer
  • Supergrass
  • Boat
  • Tic-tac
  • Zoom
  • Wet
  • Embalming fluid
  • Wack


PCP, also known as 1-(1-phenylcyclohexyl-piperidine), is classified as a dissociative anesthetic. PCP acts mainly in the central nervous system, producing both stimulation and depression. Its sympathomimetic effects are thought to be due to weak reuptake inhibition of norepinephrine and dopamine. PCP also exerts some cholinergic and anticholinergic effects and has some other actions at nicotinic and opioid receptors.

The dissociative properties of PCP are believed to be due to its actions as a glutamate antagonist at the N-methyl-D-aspartate (NMDA) receptors. NMDA antagonists have been known to produce behavioral effects similar to those observed in schizophrenia, and they are used to induce an animal model of schizophrenia for research. PCP also affects the actions of dopamine, which may cause the psychomotor effects seen with PCP.

Clinical effects occur within minutes and usually last several hours. These effects may last up to 48 hours in the event of significant overdose. However, even more prolonged effects may be seen in long-term users, either from enterohepatic recirculation or from delayed release of PCP from lipid stores. Because PCP is fat soluble, it accumulates in adipose tissue and the brain. Recurrent and fluctuating symptoms occur as PCP is remobilized from lipid stores, which can occur days, weeks, or months after the initial use. [5] The half-life of PCP is estimated at 17.4 hours; however, half-lives of 1-4 days have been reported. [6] PCP is primarily metabolized in the liver.



The Drug Abuse Warning Network (DAWN), which functioned from 1992 through 2011, estimated that PCP-related emergency department (ED) visits increased more than 400% from 2005 to 2011 (from 14,825 to 75,538 visits). PCP-related ED visits doubled from 2009 to 2011. DAWN estimates from selected metropolitan areas show geographic variation in trends, with PCP-related ED visits increasing in some areas (New York City, Chicago) while remaining stable in others (Seattle, San Francisco, Phoenix). [7]

Of PCP-related ED visits in 2011, 72% involved PCP combined with other drugs; in about half, PCP was combined with illicit drugs (32% involved marijuana and 20% involved cocaine), and in about a quarter PCP was combined with pharmaceutical agents such as pain relievers (16%) and anti-anxiety and insomnia drugs (13%).

The 2012 Monitoring the Future Survey of high school seniors showed 1.6% using PCP once in their lifetime (down from 2.13% in 2011), 0.9% had used PCP at least once in the last year, and 0.5% had used PCP at least once in the last 30 days. [8]

The 2017 National Survey on Drug Use and Health, polling persons 12 years of age and older, found that an an estimated 1.4 million people were current users of hallucinogens (LSD, PCP, peyote, mescaline, psilocybin mushrooms, MDMA (Ecstasy or Molly), ketamine, DMT/AMT/“Foxy,” and Salvia divinorum). Of adolescents aged 12 to 17, an estimated 114,000  (0.5%) were current users of hallucinogens. Adults aged 18-25 represented the largest group currently using hallucinogens, with an estimated 668,000 users (1.9%). Use among adults older than 25 was estimated at 0.3%, which represents 608,000 individuals. [9]

Doses of 20 mg or more of PCP may cause prolonged coma, seizures, and even death. One death has been reported from an ingestion of 150-200 mg in an acute overdose. In 2020, the American Association of Poison Control Centers reported 212 single exposures to PCP, with 20 major outcomes and 2 deaths. [10]

Since the identification of 3-MeO-PCP and 4-MeO-PCP as new psychoactive substances (NPS), in 2010, there have been a few case reports of  toxicity and death involving those drugs in the US and Europe. [11]  In a study of one non-fatal intoxication and 7 deaths involving 3-MeO-PCP, autopsy revealed the presence of other medications and drugs of abuse in 6 of the 7 fatal cases. [12]

DAWN estimated that males accounted for 69% of PCP-related ED visits in 2011. Approximately 45% of patients were aged 25 to 34 years. Persons aged 18 to 24 years accounted for 19% of visits, as did those aged 35 to 44. [7]



Morbidity and mortality are usually associated with rhabdomyolysis, acute kidney injury, hypertensive crises, accidental trauma, and self-destructive behavior. The outcome in cases of PCP toxicity tends to be worse in patients who present with any of the following:

  • Rhabdomyolysis
  • Acute kidney injury
  • Seizures
  • Hyperthermia
  • Hypertensive crisis
  • Traumatic injuries

Chronic PCP toxicity results in cognitive deficits and mood disorders. Patients can develop speech impediments and also suffer from dysphoria, depressionanxiety, and psychosis. [13, 14]


Patient Education

For patient education information, see the First Aid and Injuries Center and Mental Health Center, as well as Drug Dependence & AbusePoisoningClub Drugs, and Activated Charcoal. Further information is available on the following Web sites: