Large differences exist in the pharmacology of agents within the class, thus not all<unk> s are used for all indications listed below. Indications for<unk> s include: * Angina pectoris (contraindicated for Prinzmetal's angina) * Atrial fibrillation * Cardiac arrhythmia * Congestive heart failure * Essential tremor * Glaucoma (as eye drops, they decrease intraocular pressure by lowering aqueous humor secretion) * Hypertension, although they are generally not preferred as an initial treatment *Hyperthyroidism *Migraine prophylaxis * Mitral valve prolapse * Myocardial infarction * Phaeochromocytoma, in conjunction with α-blocker * Postural orthostatic tachycardia syndrome * Symptomatic control (tachycardia, tremor) in anxiety and hyperthyroidism * Theophylline overdose<unk> s have also been used for: * Acute aortic dissection * Hypertrophic obstructive cardiomyopathy * Long QT syndrome * Marfan syndrome (treatment with propranolol slows progression of aortic dilation and its complications) * Prevention of variceal bleeding in portal hypertension * Possible mitigation of hyperhidrosis * Social and other anxiety disorders *Controversially, for reduction of perioperative mortality in non-cardiac surgery, but the best evidence suggests that they increase mortality when used this way Congestive heart failure Although<unk> s were once contraindicated in congestive heart failure, as they have the potential to worsen the condition due to their effect of decreasing cardiac contractility, studies in the late 1990s showed their efficacy at reducing morbidity and mortality. Bisoprolol, carvedilol, and sustained-release metoprolol are specifically indicated as adjuncts to standard ACE inhibitor and diuretic therapy in congestive heart failure, although at doses typically much lower than those indicated for other conditions.<unk> s are only indicated in cases of compensated, stable congestive heart failure; in cases of acute decompensated heart failure,<unk> s will cause a further decrease in ejection fraction, worsening the patient's current symptoms.<unk> s are known primarily for their reductive effect on heart rate, although this is not the only mechanism of action of importance in congestive heart failure.<unk> s, in addition to their sympatholytic β1 activity in the heart, influence the renin–angiotensin system at the kidneys.<unk> s cause a decrease in renin secretion, which in turn reduces the heart oxygen demand by lowering the extracellular volume and increasing the oxygen-carrying capacity of the blood. Heart failure characteristically involves increased catecholamine activity on the heart, which is responsible for several deleterious effects, including increased oxygen demand, propagation of inflammatory mediators, and abnormal cardiac tissue remodeling, all of which decrease the efficiency of cardiac contraction and contribute to the low ejection fraction.<unk> s counter this inappropriately high sympathetic activity, eventually leading to an improved ejection fraction, despite an initial reduction in ejection fraction. Trials have shown<unk> s reduce the absolute risk of death by 4.5% over a 13-month period. In addition to reducing the risk of mortality, the numbers of hospital visits and hospitalizations were also reduced in the trials. Therapeutic administration of<unk> s for congestive heart failure ought to begin at very low doses (1/8 of target) with a gradual escalation of the dose. The heart of the patient must adjust to decreasing stimulation by catecholamines and find a new equilibrium at a lower adrenergic drive. Anxiety Officially,<unk> s are not approved for anxiolytic use by the U.S. Food and Drug Administration. However, many controlled trials in the past 25 years indicate<unk> s are effective in anxiety disorders, though the mechanism of action is not known. The physiological symptoms of the fight-or-flight response (pounding heart, cold/clammy hands, increased respiration, sweating, etc.) are significantly reduced, thus enabling anxious individuals to concentrate on the task at hand. Musicians, public speakers, actors, and professional dancers have been known to use<unk> s to avoid performance anxiety, stage fright, and tremor during both auditions and public performances. The application to stage fright was first recognized in The Lancet in 1976, and by 1987, a survey conducted by the International Conference of Symphony Orchestra Musicians, representing the 51 largest orchestras in the United States, revealed 27% of its musicians had used<unk> s and 70% obtained them from friends, not physicians.<unk> s are inexpensive, said to be relatively safe, and on one hand, seem to improve musicians' performances on a technical level, while some, such as Barry Green, the author of "The Inner Game of Music" and Don Greene, a former Olympic diving coach who teaches Juilliard students to overcome their stage fright naturally, say the performances may be perceived as "soulless and inauthentic". Surgery Low certainty evidence indicates that the use of<unk> s around the time of cardiac surgery may decrease the risk of heart dysrhythmias and atrial fibrillation. Starting them around the time of other types of surgery, however, may worsen outcomes. For non-cardiac surgery, the use of<unk> s to prevent adverse effects may reduce the risk of atrial fibrillation and myocardial infarctions (very low certainity evidence), however, there is moderate certainity evidence that this approach may increase the risk of hypotension. Low-certainity evidence suggests that<unk> s used perioperatively in non-cardiac surgeries may increase the risk of bradycardia.
Beta blocker
Calcium channel blocker
ACE inhibitor
Antiplatelet drug
Antidote
Channel blocker
Bronchial blocker
Mercurial diuretic