Alcohol abstinência is a clinically significant cluster of symptoms, behaviours and/or physiological features, varying in degree of severity and duration, that occurs upon cessation or reduction of uso of alcohol in individuals who have developed Alcohol dependência or have used alcohol for a prolonged period or in large amounts. Presenting features of Alcohol abstinência may include autonomic hyperactivity (e.g. tachycardia, hypertension, perspiration), increased hand tremor, nausea, retching or vomiting, insomnia, anxiety, psychomotor agitation, depressed or dysphoric mood, transient visual, tactile or auditory illusions or hallucinations, and distractability. Less commonly, the abstinência state is complicated by generalised tonic-clonic seizures. The abstinência state may progress to a very grave form of Delirium characterised by confusion and disorientation, delusions, and prolonged visual, tactile or auditory hallucinations. In such cases, a separate diagnosis of Alcohol-induced Delirium should also be assigned.