What Is PCP? Signs, Risks, and Overdose

PCP (phencyclidine) is a dissociative drug originally developed as a surgical anesthetic in the 1950s. Medical use was abandoned in 1965 because patients experienced severe agitation, hallucinations, and psychosis during recovery. On the street, PCP is sold as a powder, liquid, or pill. It is sometimes sprayed onto marijuana, tobacco, or mint leaves and smoked. PCP causes intense hallucinations, feelings of invincibility, aggressive behavior, and a dangerous disconnection from physical pain. Overdose can cause seizures, coma, and death. About 9,900 people search for PCP each month. This guide covers the drug’s effects, risks, and what to do in an emergency.

PCP at a Glance

• PCP is a dissociative anesthetic that distorts sight, sound, and sense of self.
• Effects begin within 2 to 5 minutes when smoked and last 4 to 8 hours. Oral doses take longer to onset and last longer.
• At low doses: euphoria, numbness, mild hallucinations. At high doses: psychosis, violence, seizures, coma.
• PCP blocks NMDA glutamate receptors and also affects dopamine and opioid systems.
• Chronic use causes persistent cognitive impairment, memory loss, and psychotic episodes.

How PCP Affects the Brain and Body

PCP’s primary action is blocking NMDA receptors, which are essential for learning, memory, and pain perception. This blockade produces the dissociative state where users feel detached from their body and environment. PCP also increases dopamine levels, contributing to its addictive potential, and interacts with opioid and sigma receptors, producing a complex pharmacological profile that makes its effects unpredictable.

The drug’s ability to block pain while increasing aggression creates a dangerous combination. People under the influence of PCP have been documented performing acts of extreme self-harm without awareness of their injuries. Emergency responders often report that individuals on PCP exhibit extraordinary strength and resistance to restraint.

Signs Someone Is Using PCP

• Blank stare and rapid, involuntary eye movements (nystagmus)
• Slurred speech or inability to communicate
• Uncoordinated, rigid, or exaggerated movements
• Numbness to pain, even from severe injuries
• Sudden, unprovoked aggression or bizarre behavior
• Profuse sweating despite normal temperatures
• Auditory and visual hallucinations
• Paranoia and extreme fear

PCP Overdose: What to Watch For

PCP overdose is a medical emergency. The drug has no specific antidote, and treatment is supportive. Signs of overdose include:

• Seizures (tonic-clonic)
• Dangerously high body temperature (hyperthermia)
• Severely elevated blood pressure
• Rhabdomyolysis (muscle breakdown that damages kidneys)
• Coma and respiratory depression
• Psychotic episode with violent or self-destructive behavior

If someone is overdosing on PCP, call 911 immediately. Keep the person in a calm, low-stimulation environment if safely possible. Do not attempt to restrain them physically unless they pose an immediate danger, as this can escalate agitation and increase the risk of injury. Overdose emergencies require professional medical response.

The DEA classifies PCP as a Schedule II controlled substance. Despite decades of decline, PCP remains available in certain regions of the United States, particularly in parts of the Northeast and Mid-Atlantic. Emergency department visits involving PCP have remained steady, with DAWN (Drug Abuse Warning Network) data showing approximately 75,000 annual ER visits related to PCP between 2018 and 2023.

Long-Term Risks of PCP Use

• Persistent psychosis: Chronic PCP use can trigger psychotic episodes that persist for weeks or months after last use.
• Cognitive decline: Memory, attention, and executive function deteriorate with repeated exposure.
• Depression and suicidal ideation: PCP withdrawal and chronic use are linked to severe depressive episodes.
• Physical harm: Pain insensitivity leads to injuries that go unnoticed and untreated.

Treatment for PCP Use

PCP addiction responds to behavioral therapies including cognitive behavioral therapy and contingency management. There are no FDA-approved medications for PCP use disorder. Treatment focuses on managing psychotic symptoms (with antipsychotic medications if needed), stabilizing mood, and building coping skills. Synthetic drug treatment programs with experience in dissociative substances provide the most effective care. If you or someone you know is using PCP, contact a treatment center or call SAMHSA’s helpline at 1-800-662-4357.