To determine the incidence, prescribing risk factors of alcohol withdrawal delirium (AWD), and factors complicating AWD, in alcohol dependent patients hospitalized for alcohol detoxification.Patients attending the detoxification program at Chiang Mai University Hospital and the Northern drug dependence treatment center between May and September 2005 were assessed. Patients with signs of AWD at baseline were excluded. Incidence, risk factors, and dosage of benzodiazepines of patients with and without subsequent AWD were compared Risk factors that prolonged the course of AWD were analyzed.Nineteen male patients were assessed. Ten patients (52.6%) developed AWD despite receiving benzodiazepine detoxification. Risk factors of age, previous history of AWD and epilepsy, alcohol use history, frequency and quantity of drinking, signs of simple withdrawal at first admission, and dosage of benzodiazepines were not significantly different between the groups. However, patients with systolic blood pressure at first admission (> 120 mmHg) had longer duration of AWD than those without abnormal blood pressure (72.0 +/- 53.7 hr versus 168.0 +/- 24.0 hr, respectively, p = 0.038).The incidence of AWD was relatively high despite treatment. Although the present study did not find any risk factor predicting AWD. AWD patients hypertensive at the first admission had significantly longer duration of delirium. Physicians should be aware of monitor and treat hypertensive state and give early treatment of alcohol withdrawal with adequate doses of benzodiazepines to decrease morbidity and mortality of AWD.