BACKGROUND The possibility that treatment with tricyclic antidepressants, in the form of dothiepin, might attenuate benzodiazepine withdrawal symptoms was investigated in a double-blind trial.
METHOD Eighty-seven non-depressed psychiatric out-patients with putative normal dose benzodiazepine dependence had their benzodiazepines reduced in stepwise amounts of 20% of the original dose for eight weeks. The patients were randomised to receive dothiepin (with dosage increasing to 150 mg/day) or placebo as an aid to withdrawal before benzodiazepine reduction and these drugs were taken for four further weeks before being stopped.
RESULTS Fewer patients entered and completed the study than expected and a Type II error was possible in the results. Although there was some evidence of withdrawal symptoms being less marked in those patients allocated to dothiepin this was independent of any antidepressant effect as depression scores were lower in the placebo group in the early phase of withdrawal (P < 0.01). Of those completing the study, greater satisfaction (P = 0.03) was recorded by those who had received dothiepin; no other differences reached statistical significance.
CONCLUSIONS Dothiepin (and by implication other tricyclic antidepressants) might have some value in reducing benzodiazepine withdrawal symptoms but does not aid drug withdrawal.