You should not use diltiazem 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.
Diltiazem is a calcium channel blocker that is used to treat hypertension (high blood pressure) or angina (chest pain).
Diltiazem injection is used to treat certain heart rhythm disorders such as atrial fibrillation or atrial flutter, or dangerously rapid heartbeats (tachycardia).
Diltiazem may also be used for purposes not listed in this medication guide.
You should not use diltiazem if you are allergic to it, or if you have:
You may not be able to receive diltiazem injection if you have certain heart rhythm conditions. Your doctor will test you for these conditions.
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 breastfeed while using this medicine.
Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.
Diltiazem oral is taken by mouth.
Diltiazem injection is given as an infusion into a vein. A healthcare provider will give you this injection. Your heart rate will be constantly monitored using an electrocardiograph or ECG (sometimes called an EKG). Your blood pressure and other vital signs will also be watched closely.
Swallow the tablet or capsule whole and do not crush, chew, or break it.
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 diltiazem suddenly. Stopping suddenly may make your condition worse.
Store at room temperature away from moisture, heat, and light.
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.
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
Overdose symptoms may include slow heartbeats or fainting.
Avoid drinking alcohol while taking diltiazem.
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.
Get emergency medical help if you have signs of an allergic reaction (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:
Common 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.
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 affect 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.
Your pharmacist can provide more information about diltiazem.