Double-blind study of metaclazepam versus diazepam treatment of outpatients with anxiety syndrome.

The therapeutic efficacy and tolerance of metaclazepam and diazepam were compared in a double-blind study of outpatients suffering from a generalized anxiety syndrome. The investigators were general practitioners. A total of 168 male and female patients aged between 18 and 60 years were included in the study and received either 15 mg metaclazepam or 15 mg diazepam per day. The analysis of tolerance was made for all 168 included patients, the evaluation of efficacy is based on the results of 131 patients (42 males and 89 females) with valid data over four weeks. During the four-week therapy period four examinations were made on days 0, 7, 14, and 28. A significant improvement of the severity of illness after administering the drugs was found for both drugs in the Clinical Global Impressions (CGI), in the Hamilton Anxiety Scale (HAMA), in the List of Complaints (B-L), and in the Adjective Checklist (EWL-K). Metaclazepam showed a statistically significant superiority over diazepam as far as the CGI items "severity of illness" and "global improvement" were concerned. Metaclazepam was slightly superior to diazepam in the two HAMA subscales "psychic anxiety" and "somatic anxiety". In the items of the selfrating scales (B-L and EWL-K) the therapeutic results of the metaclazepam group were, almost without exception, better than those of the diazepam group. A comparison of tolerance showed that metaclazepam was better tolerated. This can be seen in the greater frequency of side effects like tiredness and drowsiness under diazepam. Especially at the beginning of treatment, tiredness and drowsiness were recorded 2 1/2 times more frequently for the patients on diazepam than for those on metaclazepam.