Beta-blockers, or beta-adrenergic blockers, are a class of drugs that are used to treat a variety of conditions, including high blood pressure, glaucoma and migraines. There are several types of beta-blockers -- some affect the heart, while others influence both the heart and the blood vessels. The type of beta-blocker used depends on the age and overall health of the patient as well as the condition being treated.
Brand Names
There are more than 15 different brands of beta-blockers in the U.S. The most common brands of beta-blockers, according to the Texas Heart Institute, are Betapace (sotalol), Blocadren (timolol), Brevibloc (esmolol), Cartrol (carteolol), Coreg (carvedilol), Corgard (nadolol), Inderal (propranolol), Inderal-LA (propranolol), Kerlone (betaxolol), Levatol (penbutolol), Lopressor (metoprolol), Normodyne (labetalol), Sectral (acebutolol), Tenormin (atenolol), Toprol-XL (metoprolol), Trandate (labetalol), Visken (pindolol) and Zebeta (bisoprolol).
Function
Beta-blockers act by blocking the release of a chemical known as noradrenalin, which is released by stimulated nerves and transmits messages to different parts of the body, such as muscles, blood vessels and the heart. The Medical News Today website explains that beta-blockers help patients with heart problems and hypertension by lowering the heart rate and reducing the force of the heart muscle's contractions. Beta-blocker eye drops can be used to reduce the pressure within the eyeball by lowering the production of fluid inside the eye.
Types
There are two types beta receptors. The heart predominantly has beta 1 receptors, while beta 2 receptors control the function of smooth muscles in the body. Based on this difference between the beta receptors, beta-blockers can be classified into two major classes: non-selective beta-blockers and selective beta-blockers. According to the Cardiovascular Pharmacology Concepts website, non-selective beta-blockers block both beta 1 and beta 2 receptors and include drugs such as carteolol, carvedilol, labetalol, nadolol, penbutolol, pindolol, propranolol, sotalol and timolol. Selective beta 1 blockers block only the beta 1 receptors. This class includes acebutolol, atenolol, betaxolol, bisoprolol, esmolol, metoprolol and nebivolol.
Side Effects
Dizziness, blurred vision, confusion, headache and weakness are the most common side effects of many beta-blockers, including carvedilol and sotalol. PubMed Health states that it is important to contact a health care professional immediately if the patient experiences shortness of breath or wheezing, swelling of the feet and lower legs, or chest pain. Betapace (sotalol) is also known to cause irregular heartbeats. The patient, therefore, should be hospitalized for the initial three days of therapy to monitor the activity of the heart.
Precautions
It is important that the patient inform the physician of any known allergies to beta-blockers or if he is suffering from conditions such as asthma, diabetes or any disease of the blood vessels. PubMed Health also recommends avoiding alcoholic drinks or alcohol-based medications for two hours before and two hours after taking beta-blocker medications.
