BETA BLOCKER

in full beta-adrenergic blocking agent any of a group of synthetic drugs used to treat a wide range of diseases and conditions of the sympathetic nervous system. Stimulation by adrenalin of beta-type receptor sites, which predominate in cells of the heart and are present in vascular and other smooth muscle, results in excitation of the sympathetic nervous system. The administering of a beta blocker diminishes reaction at the beta receptor sites, thereby preventing or decreasing excitation. The drugs are prescribed to control anxiety and hypertension and to treat a variety of cardiac conditions, including anginal pain and cardiac arrythmias. The drugs have proved to be successful in reducing a patient's risk of a second heart attack.