Diltiazem MR is a calcium channel blocker, used to help manage hypertension and angina, as well as some off-label uses.

This product is better known by the brand name Cardizem, though it is available under several other brand names and numerous other generic names.

The MR in Diltiazem MR stands for modified release, meaning the medication is absorbed slower than regular-acting tablets. Other Diltiazem products are even more delayed. For comparison purposes:

• Regular Diltiazem products are taken three or four times per day.
• Diltiazem MR (this product) is taken three times per day.
• Diltiazem SR is taken twice per day.
• Diltiazem XL is taken once per day

While there are exceptions, most patients are started on lower doses of regular-acting tablets until an effective dose is found and patient tolerance to side effects are established. Once these are determined patients can think about switching to longer-acting versions, but keep in mind that they're not necessarily directly interchangeable; a doctor should be consulted before switching.

Diltiazem products should not be used in patients under age 18 without explicit doctor approval.

Taking Diltiazem MR

Officially Diltiazem MR is used to treat hypertension (high blood pressure) and angina. The medication, like all calcium channel blockers, relaxes and widens blood vessels while slowing heart rate, reducing heart beat strength, and improving blood and oxygen delivery to the heart muscle. This action reduces blood pressure and helps prevent angina.

Treatment usually starts out the same:

• Patients are usually started on 60 mg three times per day (180 mg total per day).
• After 7 to 14 days results should be evaluated and dosage increased if needed.
• Treatment should not exceed 160 mg three times per day (480 mg total per day).

While both blood pressure and angina can be monitored at home by patients, regular doctor checkups are encouraged so dosage modifications can be made if needed as well as screening for developing side effects. The lowest effective dose is preferred.

For both angina and hypertension patients are usually advised to make lifestyle changes, including:

• Dietary changes
• Adopting an exercise regimen
• Quitting smoking
• Maintaining healthy cholesterol levels
• Maintaining a healthy weight

Not all patients are able to make the above changes, but those who can are strongly encouraged to try. Diltiazem MR is not a cure, and unless the underlying cause is addressed---usually by lifestyle changes---the medication may need to be taken for the remainder of life.

Off-label Diltiazem MR may be used to manage:

• Certain heart arrhythmias
• Cluster headaches
• Raynaud's disease/phenomenon
• Tardive dyskinesia

Because calcium channel blockers reduce heart rate and heartbeat strength, Diltiazem MR can help manage certain heart arrhythmias, though it is not beneficial in all; consult a doctor before taking this medication for a heart arrhythmia.

Benefit in other conditions is likely due to the medication's vasodilation properties. Dosage and formulation can both vary widely in all off-label uses and, again, a doctor should be consulted prior to use.

Side Effects & Interactions

Most side effects associated with Diltiazem MR are mild and not cause for concern, including:

• Nausea
• Flushing
• Constipation
• Weakness
• Dizziness
• Headache

The above only need to be brought to the attention of a doctor if severe or persistant. They will usually stop occurring as the body adjusts to treatment.

More rarely more serious side effects may occur, which do warrant medical attention:

• Fainting
• Severe or persistent nausea or vomiting
• Mental or mood changes
• Severe weakness or fatigue
• Severe stomach or abdominal pain
• Jaundice
• Irregular, rapid, or pounding heartbeat

Other medications which may cause interactions with Diltiazem MR include:

• Digoxin
• Cimitidine
• Azole antifungals
• Macrolide antibiotics
• Benzodiapines
• Rifamycins
• St. John's wort
• Aprepitant
• Buspirone
• Ivabradine
• Cold or flu medications
• NSAIDs

The above is not a complete list, and taking the above does not necessarily rule out use of Diltiazem MR. However, in the interest of safety, talk with a doctor or pharmacist before mixing treatments.