Verapamil - Uses & Side effects

Verapamil is a calcium channel blocker. It works by relaxing the muscles of your heart and blood vessels.
Verapamil is used to treat hypertension (high blood pressure), angina (chest pain), and certain heart rhythm disorders.
Verapamil injection is used to rapidly or temporarily restore normal heartbeats in people with certain heart rhythm disorders.

What should you know before taking verapamil?

You should not use verapamil if you are allergic to it, or if you have a serious heart condition such as:

  • “Sick sinus syndrome” or “AV block” (unless you have a pacemaker);
  • Severe heart failure;
  • Slow heartbeats that have caused you to faint; or
  • Certain heart rhythm disorders (Wolff-Parkinson-White, Lown-Ganong-Levine syndrome).

To make sure verapamil is safe for you, tell your doctor if you have:

  • Congestive heart failure;
  • Low blood pressure;
  • Kidney disease;
  • Liver disease; or
  • A nerve-muscle disorder such as myasthenia gravis or muscular dystrophy.

It is not known whether verapamil will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

You should not breast-feed while using this medicine.

Side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • chest pain, fast or slow heart rate;
  • a light-headed feeling, like you might pass out;
  • shortness of breath (even with mild exertion), swelling, rapid weight gain;
  • fever, upper stomach pain, not feeling well; or
  • lung problems–anxiety, sweating, pale skin, wheezing, gasping for breath, cough with foamy mucus.

Common side effects may include:

  • nausea, constipation;
  • headache, dizziness; or
  • abnormal liver function tests.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

What other drugs will affect verapamil?

Many drugs can interact with verapamil. Some drugs can raise or lower your blood levels of verapamil, which may cause side effects or make it less effective. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any you start or stop using, especially:

  • aspirin, imatinib, lithium, nefazodone, St. John’s wort;
  • all other heart or blood pressure medicines, especially clonidine, digoxin, flecainide, ivabradine, nicardipine, or quinidine;
  • an antibiotic – clarithromycin, telithromycin;
  • antifungal medicine – itraconazole, ketoconazole, posaconazole, voriconazole;
  • antiviral medicine to treat hepatitis or HIV/AIDS – atazanavir, boceprevir, cobicistat, delavirdine, efavirenz, fosamprenavir, indinavir, nelfinavir, ritonavir, saquinavir;
  • a beta blocker – atenolol, carvedilol, labetalol, metoprolol, nadolol, nebivolol, propranolol, sotalol, and others;
  • cholesterol lowering medicine – atorvastatin, fluvastatin, lovastatin, pitavastatin, pravastatin, rosuvastatin, simvastatin;
  • drugs to treat high blood pressure or a prostate disorder – alfuzosin, doxazosin, prazosin, terazosin, silodosin, tamsulosin;
  • seizure medicine – carbamazepine, phenobarbital, phenytoin; or
  • tuberculosis medicine – isoniazid, rifampin.

This list is not complete, and many other drugs can interact with verapamil. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Keyword: verapamil

* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.