Protracted opioid withdrawal syndrome: This is a syndrome of less dramatic symptoms than acute withdrawals following opioid dose reduction or cessation in a patient dependent on opioids, and can persist for weeks, months or years after resolution of acute withdrawal symptoms have resolved and can sometimes worsen. The symptoms are less dramatic than acute opioid withdrawals and includes anhedonia, dysphoria, elevated anxiety, sleep disturbances, lack of energy and focus, and irritability. Persistent pain and functional limitations are prominent symptoms of protracted withdrawal syndrome.