What Are the Long-Term Risks of PCP Use?

PCP (phencyclidine) is a drug classified as a dissociative hallucinogenic drug. It was originally developed and used as an anesthetic medication, but its use resulted in the experience of psychotic symptoms in patients (hallucinations and/or delusional behaviors), and it is no longer commonly used as an anesthetic.

A dissociative drug produces an alteration in the user’s understanding of what is real. Dissociative drugs can lead to people feeling as if they are detached from their bodies or reality, or as if things outside themselves are not real. Hallucinogenic drugs may lead to alterations in the perception of reality, such that people see, hear, or otherwise experience things that are not real (hallucinations) and/or experience fixed beliefs that are not consistent with reality (delusions).

Although PCP is considered to be an extremely dangerous drug because it does have some potential medical uses, the United States Drug Enforcement Administration (DEA) classifies it in the Schedule IIcategory of controlled substances. This is the highest level of classification that medications prescribed by physicians receive. Substances classified in Schedule I are not legal to obtain by anyone except with special permissions by the government. Schedule II substances are tightly controlled and monitored, and they require a prescription by a physician as well as a sufficient reason for their distribution to private individuals. PCP is considered to be an extremely dangerous drug of abuse.

Long-Term Risks Associated with PCP Abuse

PCP’s mechanism of action involves several neurotransmitter systems or pathways, including the activation of excitatory neurotransmitters like NDMA (N-methyl-D-aspirate), acetylcholine, and other neurotransmitters, such as dopamine, endorphins, and enkephalins. The drug’s immediate effects are similar to the effects of alcohol, such that individuals may experience euphoria, giddiness, balance issues, trouble walking, and slurred speech. They may also become aggressive and experience psychotic effects. At higher doses, PCP produces confusion, sedation, catatonic-like states, and even seizures and coma. Any individual using PCP on a regular basis is most likely obtaining the drug from an illicit source and abusing it.

Numerous research studies have documented the long-term effects of PCP abuse. These effects include:

• Rapid development of tolerance (needing more of the drug to produce the desired effects)
• The development of a withdrawal syndrome, which is an unusual occurrence for a hallucinogenic drug
• The development of a substance use disorder (a hallucinogen use disorder), which can affect numerous areas of the person’s functioning, goals, and relationships
• Significant involvement in the frontal lobes of the brain, often leading to problems with attention and concentration, controlling impulses, controlling emotions, and solving problems or using judgment and rational thinking
• Emotional outbursts, impulsivity, and decision-making
• Significant damage to areas associated with learning and memory that can result in an individual having trouble learning new information
• Altered interpretation of past memories, such that the individual may remember things that never really happened
• Damage to the cerebellum (an important structure located at the posterior end of the brain that is involved in numerous aspects of physical movement and thinking), resulting in problems with intentional movements, motor control, and reasoning and judgment
• Increased potential to experience damage to other organ systems, including the cardiovascular system (leading to an increased risk for heart attack or stroke), gastrointestinal system, the kidneys, and/or the liver
• Emotional dysfunction that can include chronic issues with depression and anxiety due to the continued cycle of massive neurotransmitter release when under the influence of the drug and then massive neurotransmitter depletion after one stops using the drug
• The development of psychosis as a result of the significant alteration of massive neurotransmitter release (particularly dopamine and serotonin) followed by a significant depletion of these neurotransmitters
• The development of other co-occurring substance use disorders (e.g., alcohol use disorder, opiate use disorder, stimulant use disorder, etc.) as individuals attempt to avoid the massive neurotransmitter depletion
• Increased potential to overdose on PCP, which can occur due to the induction of severe emotional states, loss of judgment and rational thinking abilities, and the tendency for PCP users to engage in polysubstance abuse
• Involvement in the legal system, such as being charged with a crime or being the victim of a crime
• Other complications as a result of having a substance use disorder, such as financial issues, relationship issues, loss of occupation, inability to reach goals, etc.
• The need to become involved in intensive treatment in order to deal with one’s substance abuse issue
• The need to maintain a long-term recovery program and vigilance to habits and relationships in order to avoid potential relapse
• Death or disability as a result of any of the above

The risks of using and abusing PCP far outweigh any potential perceived benefits an individual may believe they will receive from use of the drug. Anyone who is abusing PCP should discuss their situation with a licensed mental health professional.

Because the discontinuation of PCP can lead to withdrawal effects, it is recommended that individuals who are using PCP on a regular basis do not attempt to discontinue the drug without first consulting a medical professional. Those who attempt to withdraw from PCP without medical assistance may be placing themselves at significant risk for harm due to potential relapse or the development of seizures. Both of these issues can be potentially fatal.

It is strongly recommended that individuals attempting to discontinue PCP enroll in a formal withdrawal management program (medical detox program) and then get involved in a long-term treatment program.