Approximately 11–15 million people report heavy alcohol use or alcohol abuse and dependence in the United States; not surprisingly alcohol related medical problems are commonly encountered in critically ill and injured patients. Alcohol withdrawal syndrome (AWS) consists of symptoms and signs arising in alcohol-dependent individuals, typically within 24–48 h of consumption of their last drink. Delirium tremens (DTs) a severe and potentially fatal form of AWS typically occurs 48–96 h after withdrawal of alcohol. AWS is usually mild and self limiting however approximately 5 % of patients develop DTs with a mortality approaching 15 %. Older age, underlying disease and comorbid liver disease are associated with an increased mortality risk. Although AWS occurs intentionally in those seeking abstinence, it may arise unexpectedly in an alcohol-dependent patients after admission to hospital. This disorder usually manifests itself on hospital day 3–5 and usually lasts under 1 week although prolonged DT’s has been described.

Alcohol affects many of the regulatory systems in the body including an increase in the release of endogenous opiates, activation of the gamma-amino-butyric acid type A receptor (GABA-A), inhibition of the N-methyl-d-aspartate (NMDA) receptor, and interactions with both serotonin and dopamine receptors. Chronic exposure to the inhibitory GABA-A and excitatory NMDA receptors are thought to be involved in the pathogenesis of alcohol withdrawal.

The key clinical findings in AWS include:

By definition in order to make the diagnosis of AWS, the patient must have two or more of the following after cessation or reduction of alcohol use that has been heavy or prolonged:

Although AWS is usually mild and does not require treatment, if severe it may be complicated by alcohol withdrawal seizures and delirium tremens. Delirium tremens (DTs), also known as alcohol withdrawal delirium, is the most severe manifestation of alcohol withdrawal, which occurs in approximately 5–20 % of patients experiencing alcohol withdrawal. DTs are characterized by:

DTs usually occurs 24–72 h after cessation of drinking, and the condition carries a 5 % mortality rate in uncomplicated patients and up to a 25 % mortality rate in patients with concomitant complications. Withdrawal seizures are a complication occurring within the first 48 h of cessation. They typically occur as a single generalized tonic-clonic seizure or a brief episode of multiple seizures. Prolongation or recurrence of seizure activity necessitates an infectious disease workup (e.g., complete blood count, lumbar puncture, blood cultures). Of the patients whose symptoms have progressed to withdrawal seizures, approximately 33 % will progress to DTs. Standard withdrawal therapy including benzodiazepines is indicated for the treatment of withdrawal seizures. Phenytoin has no role in the management of withdrawal seizures. Placebo controlled trials have demonstrated phenytoin to be ineffective in the secondary prevention of alcohol withdrawal seizures [1, 2].

AWS can be classified as: