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Tiazac

Generic Name: diltiazem (dil TYE a zem)
Brand Names: Tiazac Extended Release Capsules

Medically reviewed by P. Thornton, DipPharm Last updated on Apr 4, 2019.

What is Tiazac?

Tiazac (diltiazem) belongs to a group of drugs called calcium channel blockers. It works by relaxing the muscles of your heart and blood vessels.

Tiazac is used to treat hypertension (high blood pressure)

Tiazac is also used for the treatment of chronic stable angina. (chest pain).

Important Information

You should not use Tiazac if you have very low blood pressure, a serious heart condition such as "sick sinus syndrome" or "AV block" (unless you have a pacemaker), or if you have recently had a heart attack and you have a build-up of fluid in your lungs.

Before taking Tiazac, tell your doctor if you have kidney disease, liver disease, or congestive heart failure.

Tiazac may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert. Do not stop taking this medication without first talking to your doctor. If you stop taking this medicine suddenly, your condition may become worse.

Tiazac may be only part of a complete program of treatment that also includes diet, exercise, and other medications. Follow your diet, medication, and exercise routines very closely.

If you are being treated for high blood pressure, keep using Tiazac even if you feel well. High blood pressure often has no symptoms.

Before taking this medicine

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

  • a serious heart condition such as "sick sinus syndrome" or "AV block" (unless you have a pacemaker);

  • very low blood pressure;

  • if you have recently had a heart attack and you have a build-up of fluid in your lungs.

To make sure Tiazac is safe for you, tell your doctor if you have ever had:

It is not known whether this medicine 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.

How should I take Tiazac?

Take Tiazac extended-release capsules exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.

Swallow the capsule whole and do not crush, chew, or open the capsule.

Your blood pressure will need to be checked often and you may need frequent blood tests.

You may be given other heart or blood pressure medications to use, including nitroglycerin or a beta-blocker medicine (such as atenolol, carvedilol, metoprolol, propranolol, or sotalol). Use all medications as directed and read all medication guides you receive. Do not change your dose or dosing schedule without your doctor's advice.

Keep using your medicine even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medicine for the rest of your life.

If you need surgery, tell your surgeon you currently use blood pressure medication.

You should not stop taking Tiazac suddenly. Stopping suddenly may make your condition worse.

Store at room temperature away from moisture, heat, and light.

Tiazac dosing information

Usual Adult Dose for Hypertension:

Extended Release Capsules:
-Initial dose: 120 to 240 mg orally once a day, increasing the dose as needed
-Maintenance dose: 120 to 540 mg orally once a day
-Maximum dose: 540 mg/day

Comments:
-Once a day formulations should be taken at the same time of day, either in the morning or evening.

Usual Adult Dose for Angina Pectoris Prophylaxis:

Extended Release Capsules:
-Initial dose: 120 to 180 mg orally once a day, increasing the dose every 7 to 14 days as needed
-Maximum dose: 540 mg/day

Use:
-Treatment of chronic stable angina

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include slow heartbeats or fainting.

What should I avoid while taking Tiazac?

Avoid drinking alcohol while taking Tiazac.

Avoid taking an herbal supplement containing St. John's wort.

Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired.

Tiazac side effects

Get emergency medical help if you have signs of an allergic reaction to Tiazac (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).

Call your doctor at once if you have:

  • chest pain;

  • slow heartbeats;

  • pounding heartbeats or fluttering in your chest;

  • a light-headed feeling, like you might pass out; or

  • heart problems - swelling, rapid weight gain, feeling short of breath.

Common Tiazac side effects may include:

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.

What other drugs will affect Tiazac?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Many drugs can interact with diltiazem. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Tiazac only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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