What is Phencyclidine (PCP)?

From the Guidelines

Phencyclidine (PCP) is a highly dangerous and addictive substance with no accepted medical use, and its use can lead to severe psychological and physical effects, including overdose, seizures, coma, or death. When considering the management of patients who have used PCP, it is crucial to prioritize their safety and well-being, taking into account the potential for severe psychological effects, including paranoia, agitation, and violent behavior, as well as physical symptoms like increased heart rate, elevated blood pressure, and hyperthermia 1. The treatment for PCP intoxication typically involves supportive care in a calm environment, sometimes with benzodiazepines to manage agitation, highlighting the importance of a controlled and medically supervised setting to prevent further harm 1. Some key points to consider when dealing with PCP use include:

• The high potential for abuse and dangerous side effects, which has led to its classification as a Schedule II controlled substance
• The importance of obtaining a thorough history of the patient's current medications and illicit drug use to avoid potential drug interactions, such as the combination of phencyclidine and haloperidol, which may promote hypotension 1
• The need for long-term management and support to address potential persistent psychosis, memory problems, and speech difficulties resulting from chronic PCP use Given the severe risks associated with PCP use, it is essential to prioritize a cautious and evidence-based approach to management, focusing on minimizing harm and promoting the patient's overall well-being. In the context of real-life clinical medicine, the primary goal should be to provide supportive care, manage agitation and other symptoms, and prevent further harm, rather than attempting to use PCP or any other illicit substance for medical purposes. Overall, the use of PCP is a serious concern that requires careful attention to the patient's physical and psychological health, as well as a commitment to evidence-based management and support.

From the Research

Phencyclidine Effects

• Phencyclidine (PCP) is a drug with a broad range of pharmacological activity, causing significant medical morbidity and mortality 2.
• The clinical presentation of PCP intoxication ranges from coma to severe agitation and violence, disorientation, psychosis, catatonia, and bizarre behavior 3.
• PCP abuse can lead to serious medical complications, including rhabdomyolysis, seizures, and hyperthermia 3.
• The effects of PCP on human performance and behavior are due to its ability to alter the perception of reality in the user, causing hallucinations, delirium, disorientation, agitation, muscle rigidity, ataxia, nystagmus, seizures, and stupor 4.

Phencyclidine Intoxication

• Intoxication with low to moderate doses of PCP resembles an acute, confusing state, while high doses may cause serious neurological and cardiovascular complications 4.
• Treatment of PCP intoxication involves supportive psychological and medical measures, and acidification of the urine may further increase PCP clearance 4.
• The metabolism of PCP involves primarily hydroxylation followed by conjugation and elimination in the urine 4.

Comparison with Other Substances

• Unlike benzodiazepines, which have a depressant effect on the central nervous system, PCP has stimulant, depressant, hallucinogenic, and analgesic effects 4, 5.
• Benzodiazepines are often prescribed to control sleep disturbances, anxiety, or behavioral disinhibition, and have been shown to be beneficial in combination with antipsychotic drugs for schizophrenia 6, 5.