How should this medicine be used?
Verapamil comes as a regular tablet and as an extended-release (long-acting) tablet and capsule to take by mouth. The regular tablet is usually taken three times a day. The extended-release tablet and capsule are usually taken one or two times a day and should be swallowed whole. Do not chew, divide, or crush the extended-release tablet or capsule. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take verapamil exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Verapamil controls arrhythmias, high blood pressure, and chest pain (angina) but does not cure them. Continue to take verapamil even if you feel well. Do not stop taking verapamil without talking to your doctor.
Other uses for this medicine
Verapamil also is used to treat migraine headaches and cardiomyopathy. Talk to your doctor about the possible risks of using this drug for your condition.
What special precautions should I follow?
Before taking verapamil,
* tell your doctor and pharmacist if you are allergic to verapamil or any other drugs.
* tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially aspirin, carbamazepine (Tegretol); cyclosporine (Neoral, Sandimmune); fentanyl (Duragesic); heart and blood pressure medications such as beta-blockers, digoxin (Lanoxin), disopyramide (Norpace), flecainide (Tambocor), quinidine (Quinaglute, Quinidex), diuretics ('water pills'), or any other blood pressure lowering medication; lithium (Eskalith, Lithobid); medications to treat depression; medications to treat glaucoma (increased pressure in the eye); phenobarbital; rifampin (Rifadin, Rimactane); theophylline (Theo-Dur); and vitamins.
* tell your doctor if you have or have ever had heart, liver, or kidney disease, muscular dystrophy, or gastrointestinal obstruction (strictures).
* tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking verapamil, call your doctor.
* if you are having surgery, including dental surgery, tell your doctor or dentist that you are taking verapamil.
* you should know that verapamil may increase the effects of alcohol and make them last longer.
What special dietary instructions should I follow?
Verapamil may cause an upset stomach. Take verapamil with food or milk.
Talk to your doctor before using salt substitutes containing potassium. If your doctor prescribes a low-salt or low-sodium diet, follow these directions carefully.
What should I do if I forget a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What side effects can this medication cause?
Although side effects from verapamil are not common, they can occur. Tell your doctor if any of these symptoms are severe or do not go away:
* constipation
* dizziness or lightheadedness
* headache
* upset stomach
* heartburn
* excessive tiredness
* flushing (feeling of warmth)
* slow heartbeat
* vivid, unusual dreams
If you experience any of the following symptoms, call your doctor immediately:
* swelling of the face, eyes, lips, tongue, arms, or legs
* difficulty breathing or swallowing
* fainting
* rash
* yellowing of the skin or eyes
* fever
* increase in frequency or severity of chest pain (angina)