Pharmacokinetic research has shown that clear differences exist among benzodiazepines in rate and route of elimination and in the presence or absence of pharmacologically active metabolites. These findings and other results of pharmacokinetic research have clinical implications in terms of dosage schedules, drug accumulation during long-term therapy, antianxiety therapy in the elderly, drug interactions, pharmacotherapy in specific disease states, and the influence of route of administration on drug action.