Abstract
Alpidem, a novel imidazoโpyridine anxiolytic, was compared with lorazepam for efficacy and withdrawal effects in 23 (17 male) anxious psychiatric outโpatients of mean age 35.3 years with a mean Hamilton Anxiety Rating Scale (HAMโA) total score of 26.4. Treatment was double blind for 4 weeks with doses built up to a mean of 112.5 mg alpidem and 3.5 mg lorazepam per day. Assessment were made for a further 2 weeks after abrupt withdrawal.
There were no differences in scores between the groups before treatment. The HAMโA, Hospital Anxiety and Depression Scale, Sleep Rating Scale and other measures showed both drugs to be equally effective for psychic and somatic anxiety, depression and insomnia. Despite the small numbers, lorazepam produced greater improvement in the anxious mood, fear and insomnia items of the HAMโA. After stopping treatment serious rebound in mood and somatic scores was experienced by the lorazepam group in contrast to those patients on alpidem who maintained their improvement. Neither group was troubled by side effects; dropouts were few and due to inefficacy (1 alpidem) or withdrawal problems (2 lorazepam). Alpidem seemed to offer effective anxiolysis without the risk of rebound associated with lorazepam use.