Cardizem vs. Verelan

Are Cardizem and Verelan the Same Thing?

Cardizem (diltiazem hydrochloride) and Verelan (verapamil hydrochloride) are calcium channel blockers used for different purposes.

Cardizem is used to prevent chest pain (angina). Cardizem may help to increase your ability to exercise and decrease how often you may get angina attacks.

Verelan is used to manage hypertension (high blood pressure).

What Are Possible Side Effects of Cardizem?

Common side effects of Cardizem include:

Tell your doctor if you have unlikely but serious side effects of Cardizem including:

What Are Possible Side Effects of Verelan?

Common side effects of Verelan include:

  • constipation
  • nausea
  • skin rash
  • itching
  • dizziness
  • headache
  • tiredness, or
  • flushing (warmth, itching, redness, or tingly feeling under your skin).

Severe side effects of Verelan include heart failure, hypotension, and cardiac problems.

What Is Cardizem?

Cardizem (diltiazem hydrochloride) is a calcium channel blocker used to prevent chest pain (angina). Cardizem may help to increase your ability to exercise and decrease how often you may get angina attacks.

What Is Verelan?

Verelan (verapamil hydrochloride) is is a calcium ion influx inhibitor (slow channel blocker or calcium ion antagonist) indicated for the management of hypertension (high blood pressure).


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What Drugs Interact With Cardizem?

Cardizem may interact with amiodarone, digoxin, atazanavir, cimetidine, quinidine, St. John's wort, azole antifungals, macrolide antibiotics, rifamycins, buspirone, cyclosporine, sirolimus, statins, anti-seizure drugs, benzodiazepines, caffeine, pseudoephedrine, phenylephrine, or other drugs that can raise heart rate. Tell your doctor all medications and supplements you use.

What Drugs Interact With Verelan?

Verelan may interact with buspirone, cimetidine, clonidine, other blood pressure medications, cyclosporine, digoxin, lithium, lovastatin or simvastatin, theophylline, antibiotics, antifungals, beta-blockers, cancer medicines, cholesterol-lowering drugs, heart rhythm medications, HIV/AIDS medicines, sedatives, or seizure medications. Tell your doctor all medications and supplements you use.

How Should Cardizem Be Taken?

Dosage of Cardizem is individually adjusted. Starting with 30 mg four times daily, before meals and at bedtime, dosage is increased gradually (given in divided doses three or four times daily) at 1- to 2-day intervals until optimum response is obtained. The average optimum dosage range is 180 to 360 mg/day.

How Should Verelan Be Taken?

Verelan capsules are available in 120, 180, 240 and 360 mg strengths. Verelan sustained-release capsules are for once-a-day administration. If adequate response is not obtained with 120 mg of Verelan, the dose may be titrated upward in the following manner: (a) 180 mg in the morning; (b) 240 mg in the morning; (c) 360 mg in the morning; (d) 480 mg in the morning.


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DailyMed. Cardizem Product Information.
FDA. Verelan Product Information.

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