Diltiazem and diltiazem SR are prescription medications that are used to treat high blood pressure, chronic stable angina, and angina caused by coronary artery spasm. Diltiazem is a calcium channel blocker drug and may be prescribed to be used alone or alongside other blood pressure medications. Diltiazem works by relaxing muscles in the heart and blood vessels.

Make sure to always read the patient information and instructions before using this medication. Always follow your doctor’s directions.

• Swallow diltiazem whole without chewing or crushing.
• Diltiazem is most effective when it is taken regularly. Continue to take this medication even when you feel well.
• Do not stop taking this medication without speaking to your doctor. Stopping taking diltiazem suddenly can worsen your condition.
• This medication may be prescribed as part of a treatment program that may also include diet and exercise.

Tell your doctor and pharmacist:

• About your drug and other allergies.
• If you take any other prescription or over-the-counter medications.
• Your medical history particularly of AV block, sick sinus syndrome, heart attack, congestive heart failure, liver disease, kidney disease, low blood pressure or a build-up of fluid in the lungs.
• If you are pregnant or planning pregnancy.

You should also know:

• This medication can affect your thinking and reactions. Do not drive or operate machinery until you can do it safely.
• This medication passes into breast-milk. Do not breast-feed while taking diltiazem.
• Do not drink alcohol while taking this medication.
• Avoid grapefruit products and St John’s wort while using diltiazem.

Common side effects of diltiazem include but are not limited to:

• Headaches.
• Dizziness.
• Nausea.
• Rash.
• Weakness.

Get medical help if you have any of the following side effects of diltiazem.

• Pounding or slow heartbeat.
• Fluttering in the chest.
• Feeling lightheaded or like you might pass out.
• Signs of a liver problem including dark urine, clay-colored stools, upper stomach pain, nausea, jaundice, itching, loss of appetite, or tiredness.
• Signs of a heart problem such as swelling, rapid weight gain, or shortness of breath with mild exertion.
• Signs of a severe skin reaction including skin pain followed by a red or purple rash that may spread to the face or upper body and peels or blisters, fever, sore throat burning eyes, or swelling in the face or tongue.
• Symptoms of an allergic reaction such as difficulty breathing, hives or swelling in your face, lips, or throat.

What should I do if I miss a dose of diltiazem?

If you miss a dose of diltiazem, you should take it as soon as you remember. However, if it is almost time for your next dose, then skip your missed dose.

What is the strength of diltiazem?

Diltiazem is available in strengths of 30mg and 60mg. Diltiazem SR is available in a strength of 90mg.