DANISH MEDICAL BULLETIN ϣ Dan Med Bul / August ϤϢϣϢ ABSTRACT INTRODUCTION: Delirium tremens (DT) is a severe and potentially fatal condition that may occur during withdrawal from chronic alcohol intoxication. The purpose of the pre- sent study was to compare the effects and the rates of com- plications of phenobarbital and diazepam treatment in DT. MATERIAL AND METHODS: Data were collected retrospect- ively from the medical files of patients who had received DT treatment (n = 194) at two psychiatric departments located in the general Copenhagen area in the 1998-2006 period. At one department, all patients were treated with phenobarbi- tal (n = 53), while the treatment regimen at the other de- partment was changed from phenobarbital (n = 53) to di- azepam (n = 88) in 2002. RESULTS: Length of DT and hospitalization, mortality and rate of pneumonia (26%) were not affected by treatment. A subpopulation (9%) in the diazepam group was resistant to treatment. Respiratory depression occurred in 4% of the phenobarbital and in 1% of the diazepam-treated patients. Wernicke’s encephalopathy was established in 47% of the patients. CONCLUSION: Phenobarbital is a safe alternative to diaze- pam in the treatment of DT. In its full-blown form, delirium tremens (DT) is the most dramatic and serious of complications to alcoholism. The clinical manifestations initially comprise severe physical alcohol withdrawal symptoms such as tremor, sweating, tachycardia, increased temperature and psychomotor agitation all in response to a sufficient decrease in blood alcohol concentration. Within 0-72 hours, the patient becomes visually hallucinated and delirious with insom- nia and clouding of consciousness which typically fluctu- ates markedly over time. Withdrawal seizures are seen in approximately 20% of the patients and typically occur before the patient becomes hallucinated and delirious [1, 2]. DT is a true medical emergency with a 15% mor- tality rate [2]. World-wide, benzodiazepines seem to be the preferred drugs in DT treatment [3]. In Denmark, how- ever, barbiturates have been used in the treatment of DT for more than 100 years [4]. It has been demonstrated that barbiturates are superior to benzodiazepines in DT [5], but due to the risk of respiratory depression, some Copenhagen psychiatric departments have recently changed their treatment in favour of benzodiazepines. The purpose of the present retrospective study was to compare the effects and complications of phenobar- bital and diazepam treatment in patients who were ad- mitted with DT. MATERIAL AND METHODS Subjects were patients with DT who were admitted to the Department of Psychiatry, Rigshospitalet and the Department of Psychiatry, Bispebjerg Hospital, in the period from 1 January 1998 to 31 December 2006. The files of these patients were studied retrospectively. Repeat cases of DT in any patient were allowed. All of the following inclusion criteria had to be fulfilled: – An International Classification of Diseases 10, F10.4 diagnosis – A history of alcoholism and heavy alcohol intake within the 96 hours preceding admission – Two of the following physical alcohol withdrawal symptoms: tremor, sweat or psychomotor agitation – Visual hallucinations – A turbid and disoriented state. All patients from Rigshospitalet were treated with phe- nobarbital. At Bispebjerg Hospital, phenobarbital was used from 1 January 1998 to 31 December 2001 (four years), while patients who were admitted in the period from 1 January 2002 to 31 December 2006 (five years) were treated with diazepam. Thus, DT patients were divided into the following three groups: – PB Rigshospitalet: DT patients at Rigshospitalet who were treated with phenobarbital – PB Bispebjerg: DT patients at Bispebjerg Hospital who were treated with phenobarbital – DZP Bispebjerg: DT patients at Bispebjerg Hospital who were treated with diazepam. The phenobarbital dose was 100-200 mg hourly (admin- istered intravenously or orally), while diazepam was typ- ically administered as a 10-20 mg intravenous dose given hourly. If no effect was achieved, diazepam was adminis- ORIGINAL ARTICLE 1) Psychiatric Centre Gentofte, 2) Psychiatric Centre Bispebjerg, 3) Psychiatric Centre, Copenhagen University Hospital and 4) Danish University of Education Dan Med Bul 2010;57(8):A4169 Phenobarbital versus diazepam for delirium tremens – a retrospective study Ida Hjermø Michaelsen 1 , John Erik Anderson 2 , Anders Fink-Jensen 3 , Peter Allerup 4 & Jakob Ulrichsen 1