How do beta blockers decrease blood pressure

Main results: We included 25 RCTs that evaluated the BP lowering effects of seven nonselective beta-blockers in people with hypertension. Among the 25 RCTs, four were parallel studies and 21 were cross-over studies. Overall, nonselective beta-blockers lowered systolic BP and diastolic BP compared with placebo. Nonselective beta-blockers, in the recommended dose range, did not showed a convincing dose-response relationship by direct comparison.

The once 1x and twice 2x starting dose subgroups contained the largest sample size. The dose-response relationship in heart rate was evident by both direct and indirect comparison. Beta-blockers work by blocking the action of certain hormones in the nervous system, such as adrenaline. Adrenaline and noradrenaline are hormones that prepare the muscles in the body for exertion. This is a crucial part of responding to danger.

If the body releases high levels of adrenaline, a person may experience a rapid heartbeat, high blood pressure, excessive sweating , anxiety, and heart palpitations. Blocking the release of these hormones lowers stress on the heart and reduces the force of the contractions of the heart muscle. In turn, it also takes pressure off the blood vessels in the heart, the brain, and the rest of the body.

Beta-blockers also obstruct the production of angiotensin II, which is a hormone that the kidneys produce. This relaxes and widens the blood vessels, easing the flow of blood through them. Beta-blockers have a range of uses. The sections below outline some of them. They can help treat or prevent the following :.

In , the American Academy of Neurology and American Headache Society recommended using propranolol and metoprolol, both of which are types of beta-blocker, as a first-line therapy for preventing migraine. A review of trials from around the world concluded that propranolol was more effective than a placebo in preventing migraine and tension-type headaches.

Overall, the results suggested that this medication can reduce the number of episodes a person experiences from five to three per month.

Glaucoma is a condition in which pressure grows within the eye due to a buildup of fluid. It is a common cause of vision loss among older adults. Doctors often prescribe eye drops containing beta-blockers to lower the production of this fluid and reduce pressure within the eye.

Beta-blockers block the effects of stress hormones. As a result, they can also reduce the physical symptoms of anxiety , such as trembling and sweating. Are there any interactions? These include: Prescriptions Non-prescription drugs Inhalers Creams or ointments Over-the-counter or natural health products Alternative therapies Vitamins, minerals or supplements Herbal remedies Homeopathic medicines Traditional remedies, such as Chinese medicines Are there any side effects?

Beta-blockers can cause some side effects. Dizziness, lightheadedness, feeling faint. Beta-blockers will slow your heart rate pulse and lower your blood pressure. If you are dizzy or feel like you might faint, sit or lie down right away. Get up slowly to give your blood vessels time to adjust. Drowsiness or fatigue Unusual swelling of the feet and ankles Wheezing, trouble breathing Depression Nightmares Cold hands and feet Decreased sexual ability.

If you have side effects, talk to your pharmacist or healthcare provider. Lifestyle changes that can also help There are two ways to control and manage your heart health: medication and lifestyle. Medication can help you control heart disease and high blood pressure, but it cannot cure it. A healthy lifestyle can help you keep medication to a minimum. See more conditions. Beta blockers. Products and services. Beta blockers These drugs are often used to treat high blood pressure when other medications haven't worked.

By Mayo Clinic Staff. Thank you for Subscribing Our Housecall e-newsletter will keep you up-to-date on the latest health information. Please try again. Something went wrong on our side, please try again. Show references Types of blood pressure medications.

American Heart Association. Accessed July 14, Argulian E, et al. Misconceptions and facts about beta-blockers. The American Journal of Medicine. Whelton PK, et al. Mann JFE. Choice of drug therapy in primary essential hypertension. Accessed June 28, Sidawy AN, et al. Atherosclerotic risk factors: Hypertension. Philadelphia, Pa. Bloch MJ, et al. Antihypertensive drugs and lipids. See also Medication-free hypertension control 6 surprising signs you may have obstructive sleep apnea After a flood, are food and medicines safe to use?

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