Comparing dose levels for pentetrazol antagonism or antiaggressive activity with those causing motorial side effects in mice brotizolam (2-bromo-4-(2-chlorophenyl)-9-methyl-6H-thieno[3,2-f]-1,2,4-triazolo [4,3-alpha]-1,4-diazepine, We 941, Lendormin) showed consistently larger dose ranges than diazepam. This gives evidence that brotizolam may offer the advantage of not causing motorial side effects during therapeutic use as do many other diazepines.