Beta-blockers are medicines that work by temporarily stopping or reducing the body’s natural ‘fight-or-flight’ responses.
In turn, they reduce stress on certain parts of the body, such as the heart and the blood vessels in the brain. They lower blood pressure, protect against heart attacks, and can improve the outlook for people with heart failure.
They are prescribed for several different conditions including high blood pressure, angina, some abnormal heart rhythms, heart, anxiety, migraine, glaucoma, and overactive thyroid symptoms.
They are also sometimes known as beta antagonists, beta-adrenergic blocking agents, or beta-adrenergic antagonists.
Pharmacologist James Black won the Nobel Prize in Physiology and Medicine for his development in 1964 of the first receptor-blocking drug, propranolol, which is still in use today.
Fast facts about beta-blockers
Beta-blockers are prescribed in conditions where the heart rate needs to be slowed.
Doctors commonly recommend beta-blockers for patients with irregular heartbeats, angina, and high blood pressure.
Beta-blockers also offer relief for glaucoma, overactive thyroid, and anxiety.
There are many different brands of beta-blocker.
Taking beta-blockers can cause dizziness, cold hands and feet, weight gain, and fatigue.
Beta-blockers slow the heart beat to treat conditions in which the heart is under stress.
Beta-blockers block the hormones adrenaline and noradrenaline in the sympathetic nervous system.
The sympathetic nervous system is part of the autonomic nervous system. It activates the ‘fight-or-flight’ response.
Adrenaline and noradrenaline prepare the muscles in the body for exertion. This is a crucial part of responding to danger.
Overexposure to these hormones can be harmful. Too much adrenaline can lead to rapid heartbeat, high blood pressure, excessive sweating, anxiety, and palpitations.
Blocking the release of these hormones blockers decreases the oxygen demands and reduces stress on the heart.
This lowers the force of the contractions of the heart muscles, and of blood vessels in the heart, the brain, and the rest of the body.
Beta-blockers also obstruct the production of angiotensin II, a hormone produced by the kidneys.
Reducing the amount of angiotensin relaxes and widens the blood vessels, easing the flow of blood through the vessels.
Beta-blockers are used to treat the following:
Angina, or chest pain
Hypertension, or high blood pressure
Atrial fibrillation, or irregular heartbeat
Myocardial infarction, or heart attack
Beta-blockers can help to relieve the ‘fight-or-flight’ reactions that fuel anxiety.
Less commonly, they may be used for migraines, glaucoma, overactive thyroid, tremors, and anxiety.
The high pressure within the eyeball is reduced using beta-blocker eye drops. The medication lowers the production of fluid inside the eyeball.
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.
A person experiencing persistent anxiety, however, may also need additional treatment, such as counseling.
Hyperactive thyroid and tremor