"Angel dust", "killer weed" and "elephant tranquillizer" are some of the street names given to phencyclidine (PCP), described as one of the most dangerous drugs available today. Introduced initially as a general dissociative anaesthetic, it has unpredictable and dangerous side-effects

Although phencyclidine abuse is not associated with the development of physical dependence, it does give rise to a marked psychological dependence. A single dose, usually smoked with tobacco or other materials, can provoke a serious toxic psychosis, schizophrenic in character and accompanied by delusions, mental confusion and violent aggressive or self-destructive behaviour. Total personality changes are not uncommon, and flashback episodes occur frequently. Even total catatonic reactions are common. The unpredictability of its effects and its frequent adulteration with other hallucinogens add to the already considerable risk that is taken by anyone who tries the drug

PCP was first developed as an anaesthetic in the 1950's. Despite promising trials with animals, it turned out to make people deleterious when they woke up so the company stopped producing it. Basement chemists took over. Illicit street use of the drug has continued from the 1960's

PCP is illegally manufactured in laboratories and is sold on the street by such names as "angel dust," "ozone," "wack," and "rocket fuel." "Killer joints"and "crystal supergrass" are names that refer to PCP combined with marijuana. The variety of street names for PCP reflects its bizarre and volatile 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 turns up on the illicit drug market in a variety of tablets, capsules, and colored powders. It is normally used in one of three ways: snorted, smoked, or eaten. For smoking, PCP is often applied to a leafy material such as mint, parsley, oregano, or marijuana

At high doses of PCP, there is a drop in blood pressure, pulse rate, and respiration. This may be accompanied by nausea, vomiting, blurred vision, flicking up and down of the eyes, drooling, loss of balance, and dizziness. High doses of PCP can also cause seizures, coma, and death (though death more often results from accidental injury or suicide during PCP intoxication). Psychological effects at high doses include illusions and hallucinations. PCP can cause effects that mimic the full range of symptoms of schizophrenia, such as delusions, paranoia, disordered thinking, a sensation of distance from one's environment, and catatonia. Speech is often sparse and garbled

According to the 1996 US National Household Survey on Drug Abuse (NHSDA), 3.2 percent of the population aged 12 and older have used PCP at least once. Lifetime use of PCP was higher among those aged 26 through 34 (4.2 percent) than for those 18 through 25 (2.3 percent) and those 12 through 17 (1.2 percent)