The analgesic properties of PCP cause users to feel less pain, and persist in violent or injurious acts as a result.
Methadone users who want to come off of the drug will typically benefit from gradual cessation followed by a drug-free drug rehabilitation program.
When drug relapse occurs after treatment at a drug rehab program, some individuals may deem treatment a failure; although treatment for drug abuse typically requires continual evaluation and modification as needed, similar to the approach taken for other chronic diseases.
When an individual is experiencing the withdrawal symptoms due to a lack of heroin or other opiates, this is commonly referred to as going "cold turkey".