How Do Betablockers with Intrinsic Sympathomimetic Activity Work?

Beta-blockers with intrinsic sympathomimetic activity (ISA) are drugs used to lower blood pressure and maintain heart rate.

Beta-blockers with ISA stimulate the beta-adrenergic receptors and oppose the action of epinephrine released. Stimulation of beta-adrenergic receptors releases epinephrine, which is responsible for increased heart contraction and heart rate.

Beta-blockers with ISA decrease blood pressure and overall resistance to blood flow while maintaining the heart rate. Some drugs may also lower heart rate and contraction along with blood pressure and resistance.

Beta-blockers with intrinsic sympathomimetic activity are used to treat:

• Hypertension (high blood pressure)
• Angina (chest pain or discomfort that happens because of reduced blood flow to the heart)
• Ventricular arrhythmias (abnormal heartbeat in the lower chambers of the heart)

Beta-blockers with intrinsic sympathomimetic activity may cause the following side effects:

• Fatigue
• Headache
• Dizziness
• Shortness of breath
• Constipation
• Diarrhea
• Indigestion
• Nausea
• Abdominal pain
• Irregular heartbeat
• Chest pain
• Heart failure
• Impotence
• Muscle pain
• Itching
• Low blood pressure
• Vomiting
• Swelling
• Painful urination

The information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

Generic and brand names of beta-blockers with intrinsic sympathomimetic activity include:

• Acebutolol
• Pindolol
• Sectral
• Visken