Double-blind placebo cross-over study of long-acting (chlordesmethyldiazepam) versus short-acting (lorazepam) benzodiazepines in generalized anxiety disorders.

Chlordesmethyldiazepam a long-acting benzodiazepine was compared with lorazepam a short-acting one in a double-blind placebo cross-over study against generalized anxiety disorders. Chlordesmethyldiazepam therapy was more effective than lorazepam. Clinical efficacy, drowsiness and insomnia seem well correlated with pharmacokinetic properties of these two benzodiazepines. These results further support the use of a long-acting benzodiazepine rather than a short-acting one as an anti-anxiety agent.