Diltiazem (Cardizem)
Purpose of Medication and Method of Action
Diltiazem is used to treat both high blood pressure and to relieve symptoms of angina. It acts by blocking the calcium channel in peripheral arterioles and thus produces a relaxation of that vascular bed. This relaxation lowers blood pressure and makes it easier for the heart to pump blood. The lower effort needed by the heart to pump blood reduces its need for oxygen and reduces the liklihood of angina due to insufficient oxygen supply to the heart muscle.
Side Effects
The most common side effects are: headache, dizziness, slow heart rate (bradycardia) anmd edema.
Drug Interactions
Diltiazem may increase the blood levels of cyclosporin, carbamazepine (Tegretol) and propranolol (Inderal) blood levels and a downward dose adjustment of thosse drugs may be necessary to avoid an increased incidence of side effects. Cimetadine (Tagemet) will increase the blood levels of diltiazem.
Cautions and Contraindications
Diltiazem should not be used in those with a history of sick sinus syndrome or secondary and tertiary heart block.
Usual Dose
The usual dose is 180 to 240 mg daily.
Patient Medication Information
These information sheets do not list all known side effects of the medications, only the most common side effects. For a complete list of side effects please contact your local pharmacy or the actual drug manufacturing company.