HALLUCINOGENIC ANESTHETICS

HALLUCINOGENIC ANESTHETICS

Phencyclidine (PCP, angel dust, etc.) has a bad reputation—and deserves it. Both PCP and ketamine were initially marketed as general anesthetics under the names Sernyl and Ketalar. However, so many patients experi­enced hallucinations and delirium as they were waking up that doctors stopped using it in humans unless they received a Valium-like drug to minimize the hallucinations. Currently, ketamine is used mainly as a veterinary anesthetic. Use in humans is limited to situations in which it is essential to avoid depression of heart function with an anesthetic, or in children. PCP is sold in many different forms: as rocks that are smoked like crack, as PCP-impregnated marijuana joints, as white powder, or as pills. It is taken orally, snorted, or injected intravenously. The main effects of a single dose last four to six hours, although the effects can lin­ger for up to two days. Ketamine is usually obtained by diversion from medical use. It is typically injected, or dried powder prepared from the solution is snorted.

PCP and ketamine are among the most complicated drugs we discuss in this book, because they have so many different effects on brain activ­ity. PCP can produce a state similar to getting drunk, taking amphet­amine, and taking a hallucinogen simultaneously. It is most frequently taken for the amphetamine-like euphoria and stimulation it produces. Many of PCP's bad side effects also resemble those of amphetamine, such as increased blood pressure and body temperature. However, at the same time, it causes a "drunken" state characterized by poor coordination, slurred speech, and drowsiness. People under the influence of PCP are also less sensitive to pain. Finally, at higher doses it causes a dissociative state in which people seem very out of touch with their environment. Observers frequently report that a PCP-intoxicated person has a blank stare and seems very detached from what is going on around her.

Not surprisingly, PCP-intoxicated people frequently find themselves in trouble with the law Their driving skills are poor, their judgment worse, they are not attending to their environment, and they are insensitive to pain. This condition indeed can resemble the "drug-crazed," sometimes violent state that many misinformed people attribute to any drug of abuse. In the case of PCP, the stereotype has some truth. Few drugs cause a person to be more difficult to treat in an emergency room situation because she is so out of touch, belligerent, and agitated. At high doses, muscle rigidity and general anesthesia occur. Extremely high doses can result in coma, seizures, respiratory depression, dangerously high body temperature, and extremely high blood pressure.

Ketamine doesn't have quite the bad reputation that PCP has, perhaps because its stimulatory effects are less pronounced. People who take low doses of ketamine achieve a drunken state—they are a little spacey and uncoordinated, but more sociable. At higher doses, the intoxicated, disso­ciated feeling and loss of coordination get more intense. People describe "going down into a K-hole" to describe the feeling of being cut off from reality. They describe out-of-body and near-death experiences. This dis­sociated state is probably pretty similar to the one induced by PCP. Both of these drugs can cause amnesia, and so users often don't remember the drug experience well.