Beta blockers are medicines that affect the body's response to certain nerveimpulses. This, in turn, decreases the force and rate of the heart's contractions, which lowers blood pressure and reduces the heart's demand for oxygen.
The main use of beta blockers is to treat high blood pressure. Some also areused to relieve the type of chest pain called angina or to prevent heart attacks in people who already have had one heart attack. These drugs may also beprescribed for other conditions, such as migraine headache, tremors, and irregular heartbeat. As eye drops they are used to treat certain kinds of glaucoma.
Beta blockers, also known as beta-adrenergic blockers, are available only with a physician's prescription. Some common beta blockers are atenolol (Tenormin), metoprolol (Lopressor), nadolol (Corgard), propranolol (Inderal), and timolol (Blocadren). Eye drops that contain beta blockers include betaxolol (Betoptic), cartelol (Ocupress), and timolol (Timoptic).
The recommended dosage depends on the type, strength, and form of beta blocker, and the condition for which it is prescribed. Beta blockers may take several weeks to noticeably lower blood pressure. Taking these drugs exactly as directed is important.
Beta blockers will not cure high blood pressure, but they will help control the condition. To avoid the serious health problems that high blood pressure can cause, patients may have to take medicine for the rest of their lives. Anyone taking beta blockers for high blood pressure should not take any other prescription or over-the-counter medicine without first checking with his or her physician. Some medicines may increase blood pressure.
Some beta blockers may change the results of certain medical tests. Before having medical tests, dental work, surgery, or emergency care, anyone taking these drugs should alert the health care professional in charge.
Some people feel drowsy, dizzy, or lightheaded when taking beta blockers. Anyone who takes these drugs should not drive, use machines, or do anything elsethat might be dangerous until they have found out how the drugs affect them.Beta blockers may increase sensitivity to cold, especially in older people or people who have poor circulation.
People who usually have chest pain when they exercise may not have the pain when they are taking beta blockers. This could lead them to be more active than they should be. Anyone taking this medicine should ask his or her physicianhow much exercise and activity is safe.
People who have certain medical conditions including allergies, diabetes, emphysema, thyroid problems, who are getting allergy shots, are pregnant or breastfeeding, should discuss their condition with a doctor before starting betablockers. Effects of these drugs may be greater in people with kidney or liver disease because the medicine is cleared from the body more slowly.
Beta blockers may also worsen heart or blood vessel disease, slow heartbeat (bradycardia),myasthenia gravis (chronic disease causing muscle weakness and possibly paralysis), psoriasis (itchy, scaly, red patches of skin), and depression.
The most common side effects of beta blockers are dizziness, drowsiness, lightheadedness, sleep problems, unusual tiredness or weakness, and decreased sexual ability. In men, this can occur as impotence or delayed ejaculation. These problems usually go away as the body adjusts to the drug.
More serious side effects are possible, including breathing problems, slow heartbeat, cold hands and feet, swollen ankles, feet, or lower legs, and depression. If these symptoms appear, a doctor should be consulted promptly.
Beta blockers may interact with a number of other medicines. When this happens, the effects of one or both of the drugs may change, or the risk of side effects may be greater. Anyone who takes beta blockers should let the physicianknow all other medicines he or she is taking.