Drugs:Fact and Fiction/PCP

PCP (phencyclidine) was developed in the 1950s as an intravenous anesthetic. Its use has since been discontinued due to serious adverse effects. PCP is a white crystalline powder that is readily soluble in water or alcohol. It has a distinctive bitter chemical taste. PCP can be mixed easily with dyes and is often sold on the illicit drug market in a variety of tablet, capsule, and colored powder forms that are normally snorted, smoked, or orally ingested. For smoking, PCP is often applied to a leafy material such as mint, parsley, oregano, or marijuana. Depending upon how much and by what route PCP is taken, its effects can last approximately 4–6 hours.

Effects on the Brain
The use of PCP as an approved anesthetic in humans was discontinued in 1965 because patients often became agitated, delusional, and irrational while recovering from its anesthetic effects. PCP is a “dissociative drug,” meaning that it distorts perceptions of sight and sound and produces feelings of detachment (dissociation) from the environment and self. First introduced as a street drug in the 1960s, PCP quickly gained a reputation as a drug that could cause bad reactions and was not worth the risk. However, some abusers continue to use PCP due to the feelings of strength, power, and invulnerability as well as a numbing effect on the mind that PCP can induce. Among the adverse psychological effects reported are—


 * Symptoms that mimic schizophrenia, such as delusions, hallucinations, paranoia, disordered thinking, and a sensation of distance from one’s environment.
 * Mood disturbances: Approximately 50 percent of individuals brought to emergency rooms because of PCP-induced problems—related to use within the past 48 hours—report significant elevations in anxiety symptoms.
 * People who have abused PCP for long periods of time have reported memory loss, difficulties with speech and thinking, depression, and weight loss. These symptoms can persist up to one year after stopping PCP abuse.
 * Addiction: PCP is addictive—its repeated abuse can lead to craving and compulsive PCP-seeking behavior, despite severe adverse consequences.

Other Effects
At low-to-moderate doses, physiological effects of PCP include a slight increase in breathing rate and a pronounced rise in blood pressure and pulse rate. Breathing becomes shallow; flushing and profuse sweating, generalized numbness of the extremities, and loss of muscular coordination may occur.

At high doses, blood pressure, pulse rate, and respiration drop. This may be accompanied by nausea, vomiting, blurred vision, flicking up and down of the eyes, drooling, loss of balance, and dizziness. PCP abusers are often brought to emergency rooms because of overdose or because of the drug’s severe untoward psychological effects. While intoxicated, PCP abusers may become violent or suicidal and are therefore dangerous to themselves and others. High doses of PCP can also cause seizures, coma, and death (though death more often results from accidental injury or suicide during PCP intoxication). Because PCP can also have sedative effects, interactions with other central nervous system depressants, such as alcohol and benzodiazepines, can also lead to coma.