Predictors of Withdrawal Severity

Given the variability of alcohol withdrawal severity, it is important to monitor all patients carefully during alcohol withdrawal, particularly those at higher risk. Predicting the severity of alcohol withdrawal for an individual patient requires assessment of:

Current Drinking Patterns

No studies of the minimal level of alcohol consumption needed to produce physical dependence have been undertaken. The severity of withdrawal is only moderately predicted by amounts of alcohol consumed. In general, higher levels of consumption (for example, 150 grams of alcohol per day) is associated with greater withdrawal severity than lower levels of consumption, although people with lower levels of alcohol use (for example, 80–100 grams per day) can experience severe withdrawal and withdrawal complications. 

A predictor of increased alcohol withdrawal severity is the onset of alcohol withdrawal symptoms (such as tremor, nausea, anxiety) upon waking that are normally relieved by early morning drinking. 

Individuals with heavy but irregular (for example, 2 to 3 days per week) alcohol consumption – sometimes referred to as ‘binge’ drinking – generally do not experience severe withdrawal, although other conditions (such as epilepsy, anxiety) may be ‘unmasked’ in the period following drinking. However, patients may under-report the amount or frequency of their alcohol use. It is wise to manage such people as if they are at risk for alcohol withdrawal.

Past Withdrawal Experience

Past withdrawal experience is usually the best predictor. Patients with a history of severe alcohol withdrawal syndrome (such as severe anxiety, seizures, delirium, hallucinations) are more likely to experience such complications in future withdrawal episodes.

Concomitant Substance Use

Patients with heavy or regular use of other substances (such as benzodiazepines, stimulants, opiates) may experience more severe withdrawal features. In particular, withdrawal from both alcohol and benzodiazepines may increase the risk of withdrawal complications.

Concomitant Medical or Psychiatric Conditions

Patients with concomitant medical conditions (such as sepsis, epilepsy, severe hepatic disease, head injury, pain, nutritional depletion) or psychiatric conditions (such as anxiety, psychosis or depression) are more likely to experience severe withdrawal complications.


Chapter Recommendation Grade of recommendation
8.1 The risk of severe alcohol withdrawal should be assessed based on current drinking patterns, past withdrawal experience, concomitant substance use, and concomitant medical or psychiatric conditions. B