[Beta-blocking drugs and anxiety. A proven therapeutic value]

The therapeutic value of propranolol and other beta-adrenergic receptor blockers in anxiety disorders is reviewed. The potential side-effects of benzodiazepines, eg psychomotor impairment and dependance, suggest that the main indicators of these compounds are the acute anxiety states and the short term treatment of anxiety disorders requiring sedation. Thus, other psychotropic drugs may be of potential value in the treatment of these disorders. The results of the placebo-controlled studies reviewed here strongly suggest that propranolol is useful in the treatment of anxiety disorders, especially those: 1) characterized by the presence of somatic symptoms related to increased adrenergic tone; 2) of moderate intensity and/or seen in general practice; 3) of recent onset and not fulfilling DSM III criteria for specific chronic anxiety disorders. Propranolol and other beta-blockers may also be useful in the prevention of performance anxiety such as the fear of speaking in public or specific social phobias when limited in number in the same patients. Average therapeutic doses range from 20 to 40 mg, once to three times a day; the clinical efficacy of beta-blockers administered for periods longer than 4 weeks remains to be demonstrated. The potential impairment of cognitive functions by propranolol is still a matter of controversy as well as its ability to induce depressive states in predisposed patients. Furthermore, the efficacy of beta-blockers that do not cross the blood-brain barrier in the treatment of anxiety raises unresolved questions concerning the mode of action (central vs peripheric) of these medications. In short, beta-blocking agents, and especially propranolol, should be considered as potential therapeutic agents in the pharmacological treatment of anxiety disorders besides benzodiazepines, antidepressant compounds and the newer azapirones, eg buspirone.