isradipine vs verapamil
PlainMeds reviewed this comparison against our methodology in August 2026. It places FDA and CMS record fields side by side, without recommending either medication.
Side-by-side comparison of isradipine and verapamil. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
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Isradipine is a drug that helps lower high blood pressure. It belongs to a class of drugs called calcium channel blockers.
Verapamil is a drug that helps to lower blood pressure and treat chest pain (angina) and irregular heartbeats (arrhythmias). It works by relaxing blood vessels and slowing down the heart rate.
Isradipine capsules are used to treat high blood pressure. You can take it alone or with a thiazide diuretic (water pill). It may take 2 to 4 weeks to see the full effect.
Verapamil is used to treat chest pain called angina. This includes angina that happens when you are resting or during normal activity. It is also used to control your heart rate if you have a fast or irregular heartbeat, such as atrial fibrillation or atrial flutter. Verapamil also treats high blood pressure.
Isradipine blocks calcium from entering certain cells. This action relaxes blood vessels, which lowers blood pressure. Lowering blood pressure helps prevent strokes, heart attacks, and kidney problems.
Verapamil belongs to a class of drugs called calcium channel blockers. It works by blocking calcium from entering heart and blood vessel cells. This relaxes and widens blood vessels, which lowers blood pressure and makes it easier for the heart to pump.
- • Headache
- • Dizziness
- • Swelling in ankles or feet
- • Feeling your heart beat rapidly or irregularly
- • Fatigue
- • Constipation
- • Shortness of breath
- • Dizziness
- • Slow heart rate (less than 50 beats per minute)
- • Nausea
- Drug Interaction 32
- Dyspnoea 31
- Hypertension 29
- Acute Kidney Injury 26
- Nausea 26
- Dyspnoea 356
- Nausea 341
- Drug Interaction 316
- Dizziness 286
- Hypotension 280
If you are taking cimetidine, your doctor should watch you closely for side effects when you start isradipine. If you are taking rifampicin, isradipine may not work as well.
You should not take this medicine if you have severe heart problems, very low blood pressure, or certain types of irregular heartbeats without a pacemaker. Talk to your doctor if you have any of these conditions.
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if isradipine will harm your unborn baby. Talk to your doctor about the risks and benefits of taking isradipine while breastfeeding.
Tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. It is not known if verapamil will harm your unborn baby. Verapamil can pass into breast milk, so talk to your doctor about the best way to feed your baby if you take this medicine.
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How to Read This isradipine vs verapamil Comparison
isradipine is classified in the Calcium Channel Blocker drug class, while verapamil sits within the Calcium Channel Blocker class. Because both drugs share the same classification, they are often considered interchangeable in theory, but clinical outcomes rarely track that cleanly. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, isradipine has 144 submissions while verapamil has 1,579. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. No direct interaction between these two drugs is listed in our FDA-derived dataset, though co-prescription still warrants pharmacist review. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for isradipine or verapamil.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.