What is Cardizem SR?

Diltiazem 12-hour sustained-action capsules are used to treat high blood pressure (hypertension). Lowering high blood pressure helps prevent strokes, heart attacks, and kidney problems. Diltiazem is called a calcium channel blocker. It works by relaxing blood vessels in the body and heart so blood can flow more easily. This effect lowers blood pressure. Diltiazem may also lower your heart rate.

Take this medication by mouth with or without food, usually twice daily or as directed by your doctor. Swallow the capsules whole. Do not crush or chew the capsules. Doing so can release all of the drug at once and may increase your risk of side effects.

Your doctor may gradually increase your dose. Follow your doctor's instructions carefully. The dosage is based on your medical condition, response to treatment, and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Use this medication regularly to get the most benefit from it. To help you remember, use it at the same times each day. It is important to continue taking this medication even if you feel well. Most people with high blood pressure do not feel sick.

If this medication is used for angina, this medication must be taken regularly to be effective. It should not be used to treat angina when it occurs. Use other medications (such as nitroglycerin placed under the tongue) to relieve an angina attack as directed by your doctor. Consult your doctor or pharmacist for details.

It may take up to 2 weeks before you get the full benefit of this drug. Tell your doctor if your condition persists or worsens (for example, your routine blood pressure readings remain high or increase).

Before taking diltiazem, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: certain types of heart rhythm problems (such as sick sinus syndrome/atrioventricular block), liver disease, kidney disease, heart failure.

This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Before having surgery, tell your doctor or dentist that you are taking this medication.

Older adults may be more sensitive to the side effects of this drug, especially dizziness, constipation, or swelling ankles/feet.

This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.

This drug passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.

Dizziness, lightheadedness, weakness, nausea, flushing, constipation and headache may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

To lower the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: fainting, new or worsening symptoms of heart failure (such as shortness of breath, swelling ankles/feet, unusual tiredness, unusual/sudden weight gain), slow/irregular/pounding/fast heartbeat, mental/mood changes (such as depression, agitation), unusual dreams, severe stomach/abdominal pain, dark urine, persistent nausea/vomiting, yellowing eyes/skin.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

What special dietary instructions should I follow?
If your doctor prescribes a low-salt or low-sodium diet, follow these directions carefully.

What should I do if I forget a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.