Medications and Drugs
Beta Blockers
Pharmacy Author: Omudhome Ogbru, PharmD
Medical and Pharmacy Editor: Jay W. Marks, MD
What are beta blockers and how do they work?
Beta blockers, also known as beta-adrenergic blocking agents, are drugs that
block norepinephrine and epinephrine (adrenaline) from binding to beta receptors
on nerves. There are three types of beta receptors and they control several
functions based on their location in the body.
Beta blockers
primarily block β1 and β2 receptors. By blocking the effect of norepinephrine
and epinephrine, beta blockers reduce heart rate; reduce blood pressure by
dilating blood vessels; and may constrict air passages by stimulating the
muscles that surround the air passages to contract.
For what conditions are beta blockers used?
Beta blockers are used for treating:
They also have been found to
prevent further heart attacks and death after a heart attack.
Other uses include the treatment of
hyperthyroidism, akathisia
(restlessness or inability to sit still), and anxiety.
Some beta blockers reduce the production of aqueous humor in the
eye and therefore are used for reducing pressure in the eye caused by glaucoma.
Are there any differences between beta blockers?
Beta blockers differ in the type of beta receptors they block and, therefore,
their effects.
- Non-selective beta blockers, for example,
propranolol (Inderal), block
β1 and β2 receptors and, therefore, affect the heart, blood vessels, and air
passages.
- Selective beta blockers, for example,
metoprolol (Lopressor, Toprol XL)
primarily block β1 receptors and, therefore, mostly affect the heart and do not
affect air passages.
- Some beta blockers, for example, pindolol (Visken) have
intrinsic
sympathomimetic activity (ISA), which means they mimic the effects of
epinephrine and norepinephrine and can cause an increase in blood pressure and
heart rate. Beta blockers with ISA have smaller effects on heart rate than
agents that do not have ISA.
- Labetalol
(Normodyne, Trandate) and carvedilol
(Coreg) block beta and alpha-1 receptors.
Blocking alpha receptors adds to the blood vessel dilating effect of
labetalol (Normodyne, Trandate) and carvedilol (Coreg).
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
- metoprolol, Lopressor, Toprol XL - Learn more about Metoprolol, a drug to treat high blood pressure, heart pain, abnormal rhythms of the heart, and some neurological conditions. Information includes a description, generic and brand names, drug class and mechanism, preparations, storage, reasons for prescription, dosing, drug interactions, effect on pregnancy, and common side effects.
- Triglycerides (Test) - Learn about triglycerides, and the triglyceride test that measures triglyceride blood levels. High triglyceride levels can lead to heart attack, stroke, fatty liver, or pancreatitis.
- Congestive Heart Failure - Read about congestive heart failure symptoms like fatigue, abdomen, leg and ankle swelling, shortness of breath, sleeplessness, increased urination, nausea, abdominal pain, and decreased appetite.
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Dizziness (lightheadedness) is often caused by a decrease in blood supply to the brain,
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It is necessary for patients and health care practitioners to work together
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