Bisoprolol

GENERIC NAME: bisoprolol

DRUG CLASS AND MECHANISM
Bisoprolol belongs to a class of drugs called beta-adrenergic receptor blocking agents that also includes propranolol (Inderal), atenolol (Tenormin), and timolol (Blocadren). Bisoprolol is used for treating high blood pressure and heart pain (angina). Bisoprolol prevents the neurotransmitters (chemicals that nerves use to communicate with other nerves), norepinephrine and epinephrine (adrenaline), from binding to beta receptors on nerves. By blocking the effect of norepinephrine and epinephrine on the nerves reaching the heart and blood vessels, beta blockers reduce heart rate and the force with which the heart contracts and reduce blood pressure by dilating blood vessels but may constrict air passages by stimulating the muscles that surround the air passages. Angina occurs when the heart's need for oxygen exceeds the supply of oxygen-carrying blood. By slowing heart rate and decreasing the force with which the heart muscle contracts, bisoprolol reduces the work of the heart and the demand of the heart for oxygen. The FDA approved bisoprolol in July 1992.

PRESCRIPTION: Yes

GENERIC AVAILABLE: Yes

PREPARATIONS: Tablets: 5 and 10 mg.

STORAGE
Bisoprolol should be stored at room temperature, 59-86 F (15-30 C) in an air-tight container.

PRESCRIBED FOR
Bisoprolol is used alone or with other drugs for treating patients with high blood pressure. It also is used for treating angina and congestive heart failure.

DOSING
The usual adult dose of bisoprolol is 2.5-20 mg once daily.

DRUG INTERACTIONS
Rifampin may increase the metabolism (destruction) of bisoprolol, possibly making bisoprolol less effective. Certain calcium channel blockers, especially verapamil (Calan, Isoptin) and diltiazem (Cardizem, Tiazac), may enhance the effect of bisoprolol on the heart. In some patients, this may cause excessive slowing of the heart rate or reduce the heart's ability to beat. The use of digoxin (Lanoxin) with bisoprolol also may cause an excessive reduction in heart rate.

Nonsteroidal antiinflammatory drugs (NSAIDs) such as ibuprofen (Motrin, Advil) and naproxen (Naprosyn, Anaprox, Aleve), can reduce the blood pressure lowering effects of beta- blockers.

PREGNANCY
There are no adequate studies in pregnant women.

NURSING MOTHERS
It is not known if bisoprolol is secreted in breast milk.

SIDE EFFECTS
Bisoprolol is generally well-tolerated, and side effects are mild and transient. Side effects include abdominal cramps, diarrhea, dizziness, fatigue, depression, headache, nausea, impotence, slow heart rate, low blood pressure, numbness, tingling, cold extremities, sore throat, and shortness of breath or wheezing.

Bisoprolol can aggravate breathing difficulties in patients with asthma, or chronic bronchitis and emphysema that have a component of bronchial spasm. In patients with existing slow heart rates (bradycardias) and heart blocks (defects in the electrical conduction within the heart), bisoprolol can cause dangerously slow heart rates and even shock. Bisoprolol reduces the force of contraction of heart muscle and can aggravate symptoms of heart failure. In patients with coronary artery disease, abruptly stopping bisoprolol can suddenly worsen angina and occasionally cause heart attacks. If it is necessary to discontinue bisoprolol, its dosage can be reduced gradually over one to two weeks. Bisoprolol can mask the early warning symptoms of low blood sugar (hypoglycemia), and should be used with caution in patients receiving treatment for diabetes.