Post-acute withdrawal syndrome (PAWS) is a hypothesized set of persistent impairments that occur after withdrawal from alcohol, opiates, benzodiazepines, antidepressants and other substances. Infants born to mothers who used substances of dependence during pregnancy may also experience a post-acute withdrawal syndrome. While post-acute withdrawal syndrome has been reported by those in the recovery community, there have been few scientific studies supporting its existence outside of protracted benzodiazepine withdrawal. Because of this, the disorder is not recognized by the Diagnostic and Statistical Manual of Mental Disorders or major medical associations.

Drug use, including alcohol and prescription drugs, can induce symptomatology which resembles mental illness. This can occur both in the intoxicated state and during the withdrawal state. In some cases these substance-induced psychiatric disorders can persist long after detoxification from amphetamine, cocaine, opioid, and alcohol use, causing prolonged psychosis, anxiety or depression. A protracted withdrawal syndrome can occur with symptoms persisting for months to years after cessation of substance use. Benzodiazepines, opioids, alcohol, and any other drug may induce prolonged withdrawal and have similar effects, with symptoms sometimes persisting for years after cessation of use. Psychosis including severe anxiety and depression are commonly induced by sustained alcohol, opioid, benzodiazepine, and other drug use which in most cases abates with prolonged abstinence. Any continued use of drugs or alcohol may increase anxiety, psychosis, and depression levels in some individuals. In almost all cases drug-induced psychiatric disorders fade away with prolonged abstinence, although permanent damage to the brain and nervous system may be caused by continued substance use.