Calan (Verapamil)
This drug is a calcium channel blocker. Calcium is involved in blood vessel contraction and in controlling the electrical impulses within the heart. By blocking calcium, calan relaxes and widens blood vessels and can normalize heartbeats. Calan is used to treat chest pain (angina), high blood pressure or irregular heartbeats. Ask your doctor or pharmacist about possible problems related to use of short-acting calcium channel blockers.
This medication should be swallowed whole with a full glass of water unless your doctor directs you otherwise. This medication must be taken as directed to prevent chest pain. It is not effective if taken only when chest pain occurs. Do not stop taking this medication suddenly without your doctor's permission. Chest pain can occur if the medication is stopped too fast. Your dose may need to be gradually decreased.
Calan belongs to a class of medications, called calcium channel blockers. These medications block the movement of calcium into the muscle cells of the coronary arteries (the arteries supplying the heart) as well as the other arteries of the body. Since calcium is what triggers contraction of muscles, blocking entry of calcium relaxes the arterial muscles. This relaxation allows the arteries to become larger so that more blood can flow through them. Thus, calan is useful in treating and preventing chest pain (angina) resulting from spasm (contraction) of the coronary arteries that reduces the flow of blood to the heart. Relaxing the muscles lining the arteries in the rest of the body lowers blood pressure and thereby reduces the pressure against which the heart must pump blood. As a result, the heart works less and requires less oxygen-carrying blood. This allows the heart to work with the reduced flow of blood caused by coronary artery disease and prevents angina (which occurs whenever the flow of blood to the heart is inadequate). Calan also decreases the conduction of electrical impulses through the heart that control the coordination of contraction. As a result, the rate of contraction slows.
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
Store at room temperature away from sunlight and moisture.
