Cardiac Medications

Calcium Blockers

Calcium channel blockers are an entirely different group of medications from beta-blockers.

These agents reduce the flow of calcium into cells, which produces relaxation of blood vessel walls. These agents increase blood flow to the heart, and as well, reduce the work of the heart. They may also relax the walls of other arteries and lower blood pressure.

Calcium blockers are used for the treatment of angina and hypertension. One of the calcium blockers is also used for the treatment of arrhythmias. There has been news media attention in recent years to the question of safety of calcium channel blockers in patients with coronary artery disease and hypertension. These concerns pertain to short acting agents. There have been many studies with all classes of calcium channel blockers. In general, when used in patients who do not have congestive heart failure, the heart rate limiting calcium channel blockers ( verapamil and diltiazem) are safe to use in Coronary Artery Disease ( CAD) patients. Non heart rate limiting calcium channel blockers (nifedipine, amlodipine and felodipine) are safe to use in hypertension but are best avoided in CAD patients unless they are given with a Beta-blocker or unless the patients heart rate is naturally slow.

Side effects include headache, flushing, dizziness, lightheadedness, swelling of ankles and constipation.

Take a missed dose of this drug within four hours but do not take a double dose to make up for a missed dose. To minimize dizziness, rise slowly from a sitting or lying position. Alcohol intake can make dizziness worse. Foods and drinks containing calcium can still be included in your diet in reasonable amounts. Prevent constipation by increasing your fluid and fiber intake.

Currently available calcium blockers:

Nifedipine (Adalat XL)
Amlodipine (Norvasc)
Felodipine (Plendil, Renedil)
Verapamil (Isoptin SR, Chronovera)
Diltiazem (Cardizem CD, Tiazac)

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