PCP is addictive and its use often leads to psychological dependence, craving, and compulsive PCP-seeking behavior. Long-time users of PCP report symptoms of:

• memory loss
• difficulties with speech and learning
• depression
• weight loss that can persist up to a year after stopping PCP use.

PCP has sedative effects, and interactions with other central nervous system depressants, such as alcohol and benzodiazepines, can lead to coma or accidental overdose. Many PCP users are brought to emergency rooms because of PCP's unpleasant psychological effects or because of overdoses. In a hospital or detention setting, they often become violent or suicidal, and are very dangerous to themselves and to others. They should be kept in a calm setting and should not be left alone.