Phencyclidine (PCP)

Although phencyclidine (PCP) and drugs of similar chemical structure are often called hallucinogens, they rarely produce hallucinations. The sensory distortions or apparent hallucinations that PCP does produce are not the same type as the hallucinations produced by use of LSD . Instead, PCP belongs to a unique class of drugs often called the dissociative anesthetics. (These drugs produce a brief period of anesthesia during which individuals feel as if they are dissociated, or separated, from their bodies.) This category includes ketamine, which has recently emerged as a widely abused drug in this class. Other drugs in this class have been manufactured with effects similar to those of PCP and ketamine, and are considered early examples of "designer drugs."

PCP was developed in the 1950s as an anesthetic for veterinary surgery and the capture of wild animals and later was tested in human surgical patients. The negative side effects of PCP (such as un- pleasant feelings, disorientation, and psychotic symptoms) did not permit its regular use in medicine. In addition, the drug is no longer permitted for veterinary use because supplies were diverted, often stolen or hijacked, leading to widespread abuse in the 1970s.

One of the reasons for the popularity of PCP in the 1970s was that it was very easy to make from readily available chemicals. Now the government requires distributors of the key ingredients of PCP manufacture to keep track of sales, making it much harder to obtain PCP than it once was. Beginning in the 1980s, PCP abuse began to decrease. Use of the drug has now leveled off to considerably below what it was in the 1980s. Nonetheless, PCP is still around, and young people's use of PCP is about as common as their use of heroin. The popularity of PCP varies greatly among regions of the country, and it is used much more often by males than females.

PCP Abuse

Originally, PCP was commonly abused in tablet form (called the PeaCe Pill). When taken this way, its effects are felt within thirty minutes and usually peak in an hour or so. The intoxication lasts about four to six hours, although users may feel strange for a day or more. One reason for this method of use was that, in the early 1970s, drug sellers told people that the pills they were buying were THC (the active ingredient in marijuana), LSD, or some other hallucinogen. Because the effects of PCP were unexpected and because it was difficult to control the dose, many users experienced bad trips. People who sell PCP still try to make it more attractive by calling it THC or whatever else is currently popular.

PCP abuse increased greatly when people began to smoke and sniff it. When PCP is illegally manufactured, it usually is available in the form of a crystalline white powder. The powder is then dusted onto various kinds of leafy materials, such as parsley, mint, or marijuana. This is why PCP is often called "angel dust," or just "dust." Smoking materials containing PCP are sometimes referred to as "killer weed," "wacky weed," or just "wack." It is also possible to sniff powdered PCP or even dissolve it in water and inject it, although injecting the drug is uncommon. Users also may soak their smoking material in liquid PCP or spray it on and then let it dry before smoking. Liquid forms are sometimes colored. In addition to the ones mentioned, there are many different street names for PCP, and different regions of the country use different names for it. Of all the drugs of abuse, PCP is probably the one that a user is most likely to take without knowing what it is until it is too late.

The Effects of PCP

As with all drugs, the effects of PCP depend on the dose. Users claim that smoking the drug allows them to smoke a little, see if the effects are as strong as they like, and then smoke more if they wish. By contrast, once users take a pill, sniff it, or give themselves an injection, they are committed to that dose, whatever it is. One of the dangers of PCP, like many other illegal drugs, is the difficulty of determining the dose.

Since PCP was developed as an anesthetic, high doses can produce a kind of dissociative anesthesia in which users have trouble walking or are completely unable to walk, look and feel extremely intoxicated, and are unresponsive when people talk to them. Some people describe this effect as catatonia . Others have described this behavior as zombie-like.

The effects that PCP produces depend on the dose.

1. At low doses, users desire a feeling of dreaminess, uplifting mood, and intense or altered perceptions. Bodily perceptions are particularly affected, with users feeling somewhat numb, a little smaller or larger than usual, and dissociated from the environment. Some have described the effect as looking through the wrong end of binoculars, with everything seeming distant and unreal. Undesirable effects at low doses include impaired judgment, mood swings, panic, and partial amnesia (the inability to remember what has happened).
2. At moderate doses, users desire an increased feeling of intoxication, a feeling of being separated from their own bodies, and greater changes in perception. The undesirable effects of moderate doses include ataxia (the loss of muscle coordination, causing difficulty walking and unsteadiness), confusion, amnesia, a focus on abnormal body sensations, exaggerated mood swings, and panic.
3. At high doses, users become very intoxicated. They will typically show catatonia, blank stare, delirium , drooling, severe motor impairment (becoming uncoordinated), muscular rigidity, psychotic behavior, and amnesia. Stroke, coma, suicide, and death, most often through accidental injury, can also occur.

It is important to recognize that PCP's effects on the mind are not at all like those of marijuana or LSD. Another difference from marijuana and LSD is that PCP users will usually appear drunken and disoriented and be uncoordinated. Driving or attempting other demanding activities while under the influence of PCP is very dangerous. Users intoxicated with PCP also show bad judgment and confusion, which may lead to dangerous acts like jumping from buildings, swimming out to sea, and criminal behavior. They can be enjoying themselves and then, with little warning, become terribly frightened, act bizarrely, and become a danger to themselves and to others around them. Such people often end up in the emergency department of a hospital, with police investigations, parental notification, and other unexpected consequences.

PCP is often used with other drugs, such as marijuana, when they are smoked together. PCP users often drink alcohol or use cocaine at the same time as well. A form of PCP mixed with cocaine is sometimes referred to as "space base." The effects of PCP in combination with other drugs are not well understood. Scientists have been unable to test PCP in humans for many years because of safety concerns. People who use PCP, especially in combination with other drugs, are experimenting on themselves, with unpredictable results.

The Effects of Regular Use

PCP abusers will often increase the amount of drug they use over time, but tolerance to PCP is not nearly as great as with some other drugs of abuse, such as cocaine, LSD, and heroin. Physical dependence, with users having withdrawal symptoms when steady use of PCP is discontinued, is uncommon. Withdrawal symptoms that are sometimes reported include intense sadness, drug craving , increased appetite, and increased need for sleep.

Babies born to PCP-using mothers can be dependent on the drug. Withdrawal signs that have been noted in the newborns include diarrhea, poor feeding, irritability, jerky movements, high-pitched cry, and visual problems. In general, however, most people either do not use PCP frequently enough to become dependent in this way, or the intensity of PCP withdrawal is not severe. Nonetheless, some people develop uncontrolled use of PCP and cannot easily quit without treatment.

By far the most serious danger of PCP abuse is that it can produce long-lasting personality changes and even mental illness in some people. In fact, the effects of both short-term and long-term use of PCP so closely resemble the symptoms of schizophrenia that scientists are studying PCP effects on the brain and behavior of animals in order to learn more about this serious mental illness. Psychiatrists and psychologists refer to the serious forms of PCP mental illness as PCP psychosis , and people who develop it usually require psychiatric hospitalization and treatment with powerful antipsychotic drugs . The PCP psychosis and the milder forms of personality change that can occur in regular users often begins with depression, anxiety, paranoia , and confusion. These symptoms are sometimes seen during intoxication, but more serious problems develop if they persist beyond the period of intoxication.

There is little clear evidence of damage to organs of the body other than the brain with repeated use of PCP. In animal studies, PCP and related drugs can produce holes called vacuoles in specific regions of the brain, but it is not known if these occur in people.

Violence and PCP

PCP abuse has been associated with violence, sometimes especially gruesome acts of brutality. Scientists do not know whether PCP alone or PCP in combination with other factors causes normal people to become violent. However, PCP, like methamphetamine, is often made and sold by violent gangs. When criminals and violence-prone individuals use it, the chances of violence are increased.

Scientists do know that PCP cannot make people physically stronger. On the other hand, PCP produces numbness, decreased sensitivity to pain, impaired judgment, and paranoia; as a result of these effects, a person on PCP can become both aggressive and fearless about experiencing pain. Law-enforcement officers are trained to handle arrests of people suspected of PCP use very cautiously.

Studies comparing violence committed by people who took various drugs, such as cocaine, amphetamines, alcohol, and PCP, have generally found that PCP is no more likely than other drugs to be associated with criminal or violent behavior. In fact, the connection between abuse of alcohol, a legal and socially accepted substance, and criminal behavior is one of the most significant public-health problems, far more so than cases of PCP-related violence. Finally, it is important to recognize that PCP has a reputation for being a particularly dangerous drug, with street names like "dead on arrival," "zombie," and "killer weed." People who tend to enjoy risky behavior may try to show how tough they are by taking PCP.

Treatment of PCP Abuse or Overdose

There are currently no drugs available to directly counteract a PCP overdose or bad trips. Treatment may be given for symptoms such as suppressed breathing rates, fever, high blood pressure, increased salivation, or convulsions. PCP may be more easily eliminated from the body by making the urine more acidic and/or pumping stomach contents. Placement of overdose patients in a quiet room has helped to control violent and self-destructive behavior. Psychiatric care is usually needed for people who develop PCP psychosis. Young people who experience problems with PCP abuse can often be helped with substance abuse treatment programs designed for this age group.

see also Designer Drugs; Hallucinogens; Ketamine; Rave; Violence and Drug and Alcohol Use.