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Verapamil (By mouth)

Verapamil (ver-AP-a-mil)

Treats high blood pressure, severe angina, and arrhythmia. This medicine is a calcium channel blocker.

Brand Name(s):

Calan, Calan SR, Verelan, Verelan PM

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. Do not use it if you had an allergic reaction to verapamil.

How to Use This Medicine:

Long Acting Capsule, Tablet, Long Acting Tablet

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
  • It is best to take this medicine with food or milk.
  • Swallow the extended-release tablet or extended-release capsule whole. Do not crush, break, or chew it.
  • If you take the Verelan® or Verelan® PM extended-release capsule, you may open it and pour the medicine into a small amount of applesauce. Stir this mixture well and swallow it without chewing.
  • Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicines can affect how verapamil works. Tell your doctor if you are using any of the following:
    • Aspirin, carbamazepine, cimetidine, clonidine, cyclosporine, digitalis, digoxin, erythromycin, everolimus, ivabradine, lithium, phenobarbital, rifampin, ritonavir, sirolimus, telithromycin, temsirolimus, theophylline, vecuronium
    • Blood pressure medicine (including atenolol, metoprolol, prazosin, timolol)
    • Cancer medicines (including cisplatin, cyclophosphamide, doxorubicin, paclitaxel, prednisone, procarbazine, vindesine)
    • Diuretic (water pill)
    • Medicine for heart rhythm problem (including disopyramide, flecainide, quinidine)
    • Statin medicine
  • Do not drink alcohol while you are using this medicine.
  • Do not eat grapefruit or drink grapefruit juice while you are using this medicine.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, nerve disease, or muscle disease. Tell your doctor about all heart problems that you have.
  • This medicine may cause the following problems:
    • Heart failure
    • Low blood pressure
    • Liver problems
    • Changes in heart rhythm
  • This medicine may make you dizzy or lightheaded. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
  • Tell any doctor or dentist who treats you that you use this medicine.
  • Your blood pressure may go up if you stop using this medicine. High blood pressure usually has no symptoms. Even if you feel well, do not stop using this medicine without asking your doctor.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Chest pain, trouble breathing
  • Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
  • Fast, slow, uneven, or pounding heartbeat
  • Lightheadedness, dizziness, fainting
  • Rapid weight gain, swelling in your legs, feet, or ankles
  • Unusual tiredness or weakness

If you notice these less serious side effects, talk with your doctor:

  • Constipation

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 5/1/2020

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.

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