Phencyclidine (PCP): Overview, Effects, History, and Risks

Pharmacology and effects

PCP acts primarily as an antagonist at the N-methyl-D-aspartate (NMDA) receptor in the brain, producing analgesia, sedation and a dissociative state. In low doses it can cause numbness, slurred speech, and confusion; in higher doses it may produce hallucinations, paranoia, agitation, seizures or loss of consciousness. The drug has been associated with neurotoxic effects in experimental studies and with persistent cognitive or psychiatric problems in some users, which has led researchers to describe it as neurotoxic and capable of producing lasting changes to the brain and, in certain cases, permanent damage.

History and development

PCP was synthesized in the 1950s and briefly used as a surgical anesthetic because of its potent analgesic and dissociative properties. Clinical use was discontinued after reports of delirium and prolonged psychotic reactions in some patients. During the 1960s and 1970s it emerged as a recreational drug and acquired a variety of street names reflecting its effects and forms.

Appearance, forms and street names

In illicit markets PCP appears as a white crystalline powder or as colored tablets; its crystalline appearance has been described in simple terms as tiny crystals. It dissolves in water and in alcohol, so it is often used in solutions — a property noted in descriptions of its solubility. Common slang names include "angel dust," "embalming fluid," "horse tranquilizer" and many others; for a sampling see slang terms. A well-known method of administration is dipping or coating tobacco or cannabis cigarettes, sometimes called a "sherm," linked to the practice of dipping cigarettes in the drug.

Routes of use and detection

• Routes of administration: smoking, snorting, oral ingestion and injection.
• Common combinations: mixed with marijuana or crack to alter effects.
• Detection: PCP can be identified by specific laboratory drug tests in urine or blood but may not be detected by basic screen panels without PCP-specific assays.

Risks, treatment and legal status

PCP intoxication can be a medical emergency. Acute treatment is supportive: ensuring airway and breathing, controlling agitation and psychosis with benzodiazepines or antipsychotics when needed, and treating complications such as high blood pressure, hyperthermia or seizures. There is no specific antidote. Long-term risks include persistent cognitive impairment and an increased likelihood of mood or psychotic disorders in some users. Because of its high potential for harm, PCP is illegal in most countries and is regulated as a controlled substance.

Understanding PCP requires attention to both its immediate behavioral effects and its possible lasting neurological and psychiatric consequences. For more comprehensive resources and clinical guidance, consult specialized medical literature and national drug information services.