Overview
Calan is a prescription drug approved by the Food and Drug Administration (FDA) to treat hypertension, angina, and arrhythmias. Calan is also known by its drug name, Verapamil.

Calan is a calcium channel blocker. Calcium channel blockers are believed to work by dilating the arteries and decreasing the force with which the heart pumps.

How do I take it?
Calan is generally taken three or four times a day.

Calan comes in tablet form.

Side effects
The FDA-approved label for Calan lists common side effects including headache, dizziness, fatigue, rash, itching, tingling sensation under the skin, nausea, and constipation.

Rare but serious side effects listed for Calan include heart failure, liver damage, low blood pressure, and bradycardia (slowed heartbeat).

For more details about this treatment, visit:
Calan – RxList
http://www.rxlist.com/calan-drug.htm