What is diltiazem?

Diltiazem is in a group of drugs called calcium channel blockers. It works by relaxing the muscles of your heart and blood vessels.

Diltiazem is used to treat hypertension (high blood pressure), angina (chest pain), and certain heart rhythm disorders.

Diltiazem may also be used for other purposes not listed in this medication guide.

Precautions

You should not use this medication if you are allergic to diltiazem, or if you have:

  • certain heart conditions, especially "sick sinus syndrome" or "AV block" (unless you have a pacemaker);
  • low blood pressure; or
  • if you have recently had a heart attack.

Before taking diltiazem, tell your doctor if you are allergic to any drugs, or if you have:

  • kidney disease;
  • liver disease; or
  • congestive heart failure.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take this medication.

FDA pregnancy category C. This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Diltiazem can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

Diltiazem can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Avoid drinking alcohol while taking diltiazem.

Grapefruit and grapefruit juice may interact with diltiazem and lead to potentially dangerous effects. Discuss the use of grapefruit products with your doctor. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor.

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Instructions

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include slow heartbeat, weakness, chest pain, shortness of breath, feeling light-headed, or fainting.

Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and take only the next regularly scheduled dose. Do not take a double dose of this medication.

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Side Effects

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

Call your doctor at once if you have any of these serious side effects:

  • fast or slow heartbeats;
  • feeling light-headed, fainting;
  • fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;
  • feeling short of breath, even with mild exertion;
  • swelling, rapid weight gain; or
  • nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Less serious side effects may include:

  • stuffy nose;
  • skin rash or itching;
  • dizziness, headache, tired feeling;
  • nausea; or
  • warmth, itching, redness, or tingly feeling under your skin.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

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Interactions

Before taking diltiazem, tell your doctor if you are using any of the following drugs:

  • amiodarone (Cordarone, Pacerone);
  • buspirone (BuSpar);
  • carbamazepine (Carbatrol, Tegretol);
  • cimetidine (Tagamet, Tagamet HB);
  • cyclosporine (Gengraf, Neoral, Sandimmune);
  • digoxin (digitalis, Lanoxin, Lanoxicaps);
  • lovastatin (Mevacor);
  • rifampin (Rifadin, Rimactane, Rifater);
  • quinidine (Quinaglute, Quinidex, Quin-Release);
  • a sedative such as midazolam (Versed) or triazolam (Halcion);
  • an antibiotic such as clarithromycin (Biaxin), erythromycin (E-Mycin, E.E.S., Ery-Tab, Erythrocin), or telithromycin (Ketek);
  • an antifungal medication such as fluconazole (Diflucan), itraconazole (Sporanox), ketoconazole (Nizoral), or voriconazole (Vfend);
  • a beta-blocker such as atenolol (Tenormin), bisoprolol (Zebeta, Ziac), metoprolol (Lopressor, Toprol), propranolol (Inderal, InnoPran), sotalol (Betapace), timolol (Blocadren), and others; or
  • HIV/AIDS medicine such as amprenavir (Agenerase), atazanavir (Reyataz), delavirdine (Rescriptor), fosamprenavir (Lexiva), indinavir (Crixivan), nelfinavir (Viracept), or ritonavir (Norvir, Kaletra).

This list is not complete and there may be other drugs that can interact with diltiazem. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Other Names

Cardizem, Cardizem CD, Cardizem LA, Cardizem Monovial, Cardizem SR, Cartia XT, Dilacor XR, Diltia XT, Diltiazem Hydrochloride CD, Diltiazem Hydrochloride SR, Diltiazem Hydrochloride XR, Diltiazem Hydrochloride XT, Taztia XT, Tiazac, diltiazem, and Diltzac

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Disclaimer

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2004 Cerner Multum, Inc. Version 2.05. Revision date 8/23/04

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