Beta Blockers

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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. Norephinephrine and epninephrine are produced by nerves throuought the body as well as by the adrenal gland. They serve as neurotransmitters (chemicals that nerves use to communicate with one another ), and also are released into the blood. There are three types of beta receptors and they control several different functions based on their location in the body.

  • beta-1 (β1) receptors are located in the heart, eye, and kidneys;
  • beta (β2) receptors are found in the lungs, gastrointestinal tract, liver, uterus, blood vessels, and skeletal muscle; and
  • beta (β3) receptors are located in fat cells.

Beta blockers primarily block β1 and β2 receptors and thereby and thereby the effects of norepinephrine and epinephrine. By blocking the effects 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 considered an adverse side effect.

What are some examples of beta blockers?

What are the side effects of beta blockers?

Medically Reviewed by a Doctor on 10/21/2013



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