Beta Blockers Drug Information

Heart Disease (Coronary Artery Disease) Slideshow

Pharmacy Author: Annette Gbemudu, PharmD
Medical Editor: Jay W. Marks, MD

• What are beta blockers and how do they work?
• For what conditions are beta blockers used?
• Are there differences among beta blockers?
• What are the side effects of beta blockers?
• What are the drug interactions?
• What are some examples of beta blockers?

What are beta blockers and how do they work?

Beta blockers, also known as beta-adrenergic blocking agents, are a class of drugs that works by blocking the neurotransmitters norepinephrine and epinephrine from binding to receptors. There are three known types of beta receptors, known as beta₁ (β₁), beta₂ (β₂) and beta₃ (β₃).

• β₁-adrenergic receptors are located commonly in the heart and kidneys.
  
  
• β₂-adrenergic receptors are located mainly in the lungs, gastrointestinal tract, liver, uterus, vascular smooth muscle, and skeletal muscle.
  
  
• β₃- adrenergic receptors are located in fat cells.

When the neurotransmitters are prevented from binding to the receptors, it in turn causes the effects of adrenaline (epinephrine) to be blocked. This action allows the heart to relax and beat more slowly thereby reducing the amount of blood that the heart must pump. Over time, this action improves the pumping mechanism of the heart.