22nd July 2023

Alcohol withdrawal syndrome

Clinical features

People with alcohol dependence are at risk of developing alcohol withdrawal syndrome when they stop or suddenly reduce their alcohol intake.

Alcohol interacts with both GABA and NMDA receptors; chronic use can lead to dysregulation of these receptors. If alcohol consumption is drastically reduced or ceased, this leads to an excess of glutamatergic activity, with reduced GABA activity, which results in overstimulation of the sympathetic nervous system.

Common clinical features of withdrawal include sweating, anxiety, nausea, vomiting, tachycardia and palpitations.

Severe alcohol withdrawal can manifest as ‘delirium tremens’. This is an acute confusional state associated with visual hallucinations, delusions and a coarse tremor. It typically develops 48 hours after the patient’s last drink. This is a medical emergency and can be life-threatening.

Additionally, severe alcohol withdrawal can also cause seizures, which typically manifest 72 hours after the last drink.

Assessment and diagnosis

It is crucial to identify patients with alcohol dependence so that alcohol withdrawal can be monitored for and treatment preempted.

When alcohol withdrawal syndrome is suspected, the severity of symptoms should be assessed in order to guide treatment. The Clinical Institute Withdrawal Assessment for Alcohol Revised (CIWA-Ar) is a validated scoring system to assess severity and is based on key clinical features associated with alcohol withdrawal. (See the References section for more information.

Although alcohol withdrawal is a clinical diagnosis, other investigations should be carried out to support the diagnosis, but also exclude other causes of the presentation.

Management

The mainstay of management of alcohol withdrawal is benzodiazepines. Emergency treatment for seizures is intravenous lorazepam, and delirium tremens can be treated with oral lorazepam or diazepam. Antipsychotics may be used if there is a poor response to benzodiazepines.

For those without seizures or delirium tremens, a benzodiazepine regimen should be initiated. In the majority of people, this would be with chlordiazepoxide, which is a longer-acting benzodiazepine than diazepam and lorazepam.

In addition, all patients should be given thiamine to prevent or treat Wernicke’s encephalopathy. Initially, a high dose parental form is recommended, commonly known as the brand name Pabrinex. Local protocols differ in their recommendations on how long intravenous thiamine should be continued; the patient should then subsequently be established on an oral formulation long term.