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Ketamine and Phencyclidine (PCP)


Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Grand Strand Medical Center

Reviewed/Revised Dec 2022

Ketamine and phencyclidine are N-methyl-D-aspartate receptor antagonists and 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 Hallucinogens Hallucinogens are a diverse group of drugs that can cause unpredictable, idiosyncratic reactions. Intoxication typically causes hallucinations, with altered perception, impaired judgment, ideas... read more 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 are used therapeutically for sedation, pain control, and depression Treatment Depressive disorders are characterized by sadness severe enough or persistent enough to interfere with function and often by decreased interest or pleasure in activities. Exact cause is unknown... read more .

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 smoking tobacco.

Symptoms and Signs of Ketamine or PCP Use

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Overdose causes a withdrawn state of depersonalization and disassociation; when doses are higher, disassociation can become severe and response to external stimuli is impaired, with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. Although rare, ketamine may induce brief or recurrent laryngospasm even at a therapeutic dose.

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

Emergence reaction is an adverse reaction to PCP and ketamine use seen during the recovery phase. It manifests with bizarre behavior, psychosis, confusion, hallucinations, vivid dreams, or the sensation of floating. Some symptoms may last for weeks.

Development of tolerance and dependence to PCP have been seen in animal studies. Psychologic dependence on ketamine has been reported.

Some patients may develop withdrawal symptoms from ketamine such as anxiety, sweating, and palpitations. Lower urinary tract symptoms such as dysuria, urinary frequency, and hematuria have been reported among long-term ketamine users. Frequent use of ketamine may cause long-term memory impairment.

Diagnosis of Ketamine or PCP Use

  • Usually a clinical diagnosis

Diagnosis is usually clinical. Some facilities may carry the urine immunoassay that detects PCP. Ketamine is not detected by routine urine drug screens Drug Testing Drug testing is done primarily to screen people systematically or randomly for evidence of use of one or more substances with potential for abuse. Testing may be done in the following: Certain... read more ; gas chromatography and mass spectroscopy testing can be requested when ketamine use must be confirmed.

Treatment of Ketamine or PCP Use

  • 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

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • Listing of licensed US providers of treatment for substance use disorders.

Drugs Mentioned In This Article

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NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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