Relapse means that a person has returned to drinking or using drugs after having successfully quit. Most people who stop drinking or using drugs because of abuse or dependence have at least one relapse.
Relapses are most likely to happen in the first few months after drinking or drug use has stopped. A person may have several relapses regardless of whether he or she has received professional treatment. But as time goes on, relapses usually occur less often and do not last as long. Having a relapse is not a reason to give up on treatment for alcohol or drug abuse and dependence.
WebMD Medical Reference from Healthwise