Drug Name

Verapamil

Drug Uses

Verapamil is used for treating supraventricular tachycardia, a rhythm disturbance of the heart. It is also used for controlling heart rate response to other rhythm disturbances, specifically atrial fibrillation and atrial flutter. It may also be used for other conditions as determined by your doctor.

Drug Class and Mechanism

Verapamil is a calcium channel blocker. It works by slowing the electrical conduction in the heart, slowing heart rate, and/or normalizing heart rhythm.

Warnings/Precautions

Do NOT use Verapamil if:

• you are allergic to any ingredient in Verapamil
• you have certain heart problems (eg, left ventricular dysfunction, sick sinus syndrome, second- or third-degree heart block and do not have a pacemaker); very low blood pressure; or moderate to severe congestive heart failure (CHF)
• you have atrial fibrillation or flutter and a pre-excitation syndromes (extra conduction pathway in the heart), such as Wolff-Parkinson-White syndrome (WPW) or Lown-Ganong-Levine syndrome (LGL)
• you have shock due to serious heart problems
• you are taking dofetilide

Contact your doctor or health care provider right away if any of these apply to you.

Before using Verapamil:
Some medical conditions may interact with Verapamil . Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

• if you are pregnant, planning to become pregnant, or are breast-feeding
• if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
• if you have allergies to medicines, foods, or other substances
• if you have heart failure or a recent heart attack with lung congestion; low blood pressure; heart problems (eg, a very slow heart rate, heart block, heart valve disease)
• if you have kidney or liver problems, muscular dystrophy, or a neuromuscular disease
• if you are taking another blood pressure medicine

Some MEDICINES MAY INTERACT with Verapamil. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Beta-blockers (eg, propranolol), disopyramide, ketolides (eg, telithromycin), or macrolides (eg, erythromycin) because the actions and the risk of side effects of Verapamil, some potentially life-threatening, may be increased
• Phenobarbital, rifampin, or St. John's wort because they may decrease Verapamil 's effectiveness
• Aldosterone blockers (eg, eplerenone), beta-blockers (eg, propranolol), other blood pressure medicines, carbamazepine, colchicine, cyclosporine, digitoxin, digoxin, dofetilide, dronedarone, eletriptan, erythromycin, everolimus, flecainide, HMG-CoA reductase inhibitors (eg, lovastatin, simvastatin), lithium, narcotic pain relievers (eg, fentanyl), nondepolarizing muscle relaxants (eg, atracurium), quinazolines (eg, metolazone), quinidine, ranolazine, theophyllines, or tolvaptan because the actions and the risk of side effects, some potentially life-threatening, may be increased by Verapamil

This may not be a complete list of all interactions that may occur. Ask your health care provider if Verapamil may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

Possible Side Effects

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Dizziness; fatigue; headache; lightheadedness.

Seek medical attention right away if any of these SEVERE side effects occur:
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); chest pain; lightheadedness, especially when standing; severe dizziness; shortness of breath; swelling of the feet or hands; unusually fast, slow or irregular heartbeat.

More Information

If you have any questions about Verapamil, please talk with your doctor, pharmacist, or other health care provider.
Verapamil is to be used only by the patient for whom it is prescribed. Do not share it with other people.
If your symptoms do not improve or if they become worse, check with your doctor.