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PCP

In the 1960s it was marketed again, this time to veterinarians strictly as an animal anesthetic and tranquillizer. It was at this time that San Francisco's drug subculture discovered the drug and nicknamed it the "peace pill" - possibly hence the name PCP. (Scientifically, PCP is an abbreviation for the drug's chemical name, phenylcyclohexylpiperidine.) On the street it also became known as angel dust, crystal, hog, or horse tranquillizer.

PCP is no longer used by veterinarians and is produced today only in illicit laboratories. A synthetic drug (chemically unrelated to LSD or mescaline), PCP is a white crystalline powder, readily soluble in water or alcohol. On the street, it is sold in the form of pills, capsules, or powder.

The drug can be taken orally - as a liquid, tablet, or capsule. It is also "snorted" (sniffed), or smoked in "joints" mixed with tobacco, marijuana, or dried parsley. It can also be taken intravenously. If it is injected, unsterile needles may cause infections. Those sharing needles with other users risk hepatitis or AIDS (acquired immune deficiency syndrome).

PCP is difficult to classify accurately, since different doses produce different effects - such as those derived from stimulants, hallucinogens, anesthetics, or analgesics (painkillers). Not all people react the same way to the drug, even after taking the same amount.

Effects

• the amount taken at one time
• the user's past drug experience
• the manner in which the drug is taken
• the circumstances under which the drug is taken (the place, the user's emotions and activities, the presence of other people, the simultaneous use of alcohol or other drugs, etc.).

Moreover, since the content of PCP varies widely from one street product to another, the intensity and duration of its effects cannot be predetermined. In street samples analysed at the Addiction Research Foundation, PCP content ranged from 1.3 to 81 mg per unit dose.

Short-term effects appear soon after taking a single dose of PCP, and disappear within a few hours or days.

At low doses (e.g. 5 mg or less), the physical effects of PCP may include: shallow and rapid breathing, increased blood pressure and heart rate, a marked rise in temperature, profuse sweating, and a numbness in arms and legs. At higher doses (e.g. 10 mg or more), there is a rapid drop in blood pressure, heart rate, and respiration, which in turn is accompanied by nausea, vomiting, blurred vision, dizziness, and decreased awareness of pain. Muscles contract so intensely they cause jerky, uncoordinated movements and bizarre postures. Heavy doses of the drug can cause convulsions and coma.

PCP's effects on the brain inhibit the user's ability to concentrate, to think logically, and to articulate. Dramatic changes in perception, thought, and mood occur. While some users experience mild to intense euphoria, others feel threatened and because of fear, anxiety, or panic - can behave violently. The drug may also release hidden emotional or mental problems.

Among the effects of higher doses - which mimic certain symptoms of schizophrenia and can take two weeks to disappear - are delusions, hallucinations (mainly auditory), and a sensation of distance from one's environment. Most regular users admit having had at least one "bad trip." But the hope of achieving the extraordinary "high" that PCP can bring is powerful enough to keep them taking the drug.

Some deaths have been directly linked to PCP overdoses (with amounts between 150 and 200 mg); others have been linked to the drug's psychological impact - causing accidental drownings, suicides, homicides, and car crashes.

Little is known about PCP's long-term effects, which appear after repeated use over a lengthy period. Some users suffer unpleasant "flashbacks" similar to those experienced by LSD users. These are unpredictable, spontaneous recurrences of the original PCP trip without the user's having taken the drug again. Flashbacks can occur weeks, months, or even up to a year after the last encounter with the drug. Typically, they last only a few minutes, and are usually visual images ranging from formless colors to frightening hallucinations.

After prolonged use, persistent speech problems, loss of memory (particularly recent memory), and severe, long-lasting anxiety, depression, and social withdrawal have also been noticed in users.

Tolerance and dependence

Psychological dependence is suggested by the compulsive daily consumption of, and craving for, the drug by some users.

There is no physical dependence on PCP after continuous use, for there are no withdrawal symptoms after the drug is discontinued.