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Ketamine and Phencyclidine (PCP)


Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Albert Einstein Medical Center

Last full review/revision May 2020| Content last modified May 2020
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Ketamine and phencyclidine are dissociative anesthetics that can cause intoxication, sometimes with confusion or a catatonic state. Overdose can cause coma and, rarely, death.

Ketamine and phencyclidine (PCP) are chemically related anesthetics. These drugs are often used to adulterate or pass for other hallucinogens such as lysergic acid diethylamide (LSD).

Ketamine is available in liquid or powder form. When used illicitly, the powder form is typically snorted but can be taken orally. The liquid form is taken IV, IM, or subcutaneously. IM and IV ketamine is increasingly being used therapeutically for sedation and pain control.

PCP, once common, is no longer being legally manufactured. It is illegally manufactured and sold on the street under names such as angel dust; it is sometimes sold in combination with herbs, marijuana, and tobacco.

Symptoms and Signs

Intoxication, characterized by a giddy euphoria, occurs with lower doses; euphoria is often followed by bursts of anxiety or mood lability.

Overdose causes a withdrawn state of depersonalization and disassociation; when doses are higher still, disassociation can become severe and response to external stimuli is impaired, with combativeness, ataxia, dysarthria, muscular hypertonicity, nystagmus, hyperreflexia, and myoclonic jerks. With very high doses, acidosis, hyperthermia, tachycardia, severe hypertension, seizures, and coma may occur; deaths are unusual.

Acute effects generally fade rapidly and many patients regain normal consciousness in 45 minutes to several hours.


  • Clinical evaluation

Diagnosis is usually clinical. Ketamine is not detected by routine urine drug screens; gas chromatography and mass spectroscopy testing can be requested when ketamine use must be confirmed.


  • Supportive measures

Users of ketamine and phencyclidine (PCP) should be kept in a quiet, calming environment and closely observed. Benzodiazepines can be used to manage agitation and seizures. Further treatment is rarely needed.

More Information

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