Halazepam and diazepam in neurotic anxiety: A double-blind study

Halazepam (160 mg/day) was compared to diazepam (20 mg/day) and to a placebo in a double-blind study with anxious neurotic outpatients from general family practice and a symptomatic volunteer clinic. One hundred twenty-five patients completed at least 4 weeks of treatment. Halazepam produced the most amount of side effects followed by diazepam, while placebo produced the least amount of side effects. Sedation was the most frequently reported side effect.No significant drug x population interaction effects were found and only very few population effects occurred indicating SVC patients to improve more than GP patients. Treatment differences indicate diazepam to be slightly more effective than halazepam, and both drugs to be superior to placebo according to several outcome criteria. At the 6-week period, diazepam, in fact, was significantly more effective than halazepam according to physician and patient questionnaire ratings. Global ratings of improvement, however, indicated both drugs to be equally effective and to produce significantly more improvement than placebo.Initial levels of anxiety and depression were found to have a differential effect on treatment outcome. Anxious patients with little secondary depression improved more than patients with more marked secondary depression regardless of treatment agent prescribed. High anxious halazepam-treated patients were found to improve significantly more than low anxious halazepam-treated patients, while initial level of anxiety showed little effect on the diazepam response. It would thus seem that in the present study diazepam (20 mg/day) was slightly more efficacious in reducing anxious symptomatology than halazepam (160 mg/day) and particularly in the only mildly anxious patient. Perhaps a daily dosage of 120 mg/day of halazepam might have been more appropriate for most anxious patients.