Alcohol Withdrawal Syndrome (AWS)
Overview and epidemiology
Alcohol Withdrawal Syndrome (AWS) is the clinical spectrum that follows reduction or cessation of prolonged heavy alcohol use. Presentations range from mild anxiety and tremor to life‑threatening complications such as generalized seizures and delirium tremens (DT).
Around 8-11% of inpatients with alcohol use disorder (AUD) will develop clinically significant AWS during admission. Early recognition, appropriate monitoring and timely treatment in the emergency department (ED) reduce morbidity and mortality (NICE CG100, CG115; RCEM toolkit).
Pathophysiology (concise)
Chronic ethanol exposure enhances GABAergic inhibition and inhibits NMDA‑mediated excitation. The brain adapts by downregulating GABA receptors and upregulating NMDA receptors.
When alcohol intake falls, this produces a relative loss of inhibition and excessive excitation, resulting in central nervous system hyperexcitability that causes the clinical features of AWS. Symptoms may begin while blood alcohol is still detectable; withdrawal is triggered by the relative fall in ethanol level.
Clinical features and timeline Typical time course
- 6-12 hours: autonomic hyperactivity (tachycardia, sweating), tremor, anxiety, insomnia, nausea and vomiting.
- 12-48 hours: alcohol hallucinosis (usually visual) may occur without global disorientation.
- 24-48 hours: generalized tonic-clonic seizures most commonly occur in this window.
- 48-72 hours (occasionally later): Delirium Tremens (DT) - fluctuating global confusion, marked autonomic disturbance, agitation and hallucinations; highest risk of complications and death.