Beta-Blocker Therapy

Beta blocker therapy is the use of beta blockers, also called beta adrenergic receptor antagonists, a class of medications predominantly used to manage abnormal heart rhythms and to protect the heart from a second heart attack after a first one. Beta blockers are also used widely to treat high blood pressure, though they are no longer the first choice for initial treatment of most people, and they can be used to treat anxiety, a notable example being the situational use of propranolol to dampen the physical symptoms of performance anxiety. Beta blockers work as competitive antagonists that block the receptor sites for the hormones epinephrine and norepinephrine on beta adrenergic receptors of the sympathetic nervous system, which mediates the body's fight or flight response, and some beta blockers block all types of beta adrenergic receptor while others are selective for one of the three known receptor types. In 1964 the pharmacologist James Black synthesized the first clinically significant beta blockers, propranolol and pronethalol, which revolutionized the medical management of angina pectoris and are considered by many to be one of the most important contributions to clinical medicine and pharmacology of the twentieth century.