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diltiazem vs felodipine

Side-by-side comparison of diltiazem and felodipine Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

Drug Class
diltiazem Calcium Channel Blocker
felodipine Calcium Channel Blocker
Type
diltiazem Prescription
felodipine Prescription
Summary
diltiazem

Diltiazem is a medicine that helps lower high blood pressure and prevent chest pain. It belongs to a class of drugs called calcium channel blockers.

felodipine

Felodipine is a drug that lowers your blood pressure. Lowering blood pressure reduces the risk of strokes and heart attacks.

What It Treats
diltiazem

Diltiazem is used to treat high blood pressure. It can be used alone or with other blood pressure medicines. Diltiazem also helps manage chronic stable angina (chest pain) and angina caused by spasms in the heart's blood vessels.

felodipine

Felodipine treats high blood pressure (hypertension). Lowering your blood pressure helps prevent strokes and heart attacks. It's important to also manage other risk factors like cholesterol, diabetes, and smoking. You may need more than one medicine to control your blood pressure.

How It Works
diltiazem

Diltiazem works by relaxing blood vessels, which lowers blood pressure. It also reduces the heart's workload, which can prevent chest pain. This medicine blocks calcium from entering heart and blood vessel cells.

felodipine

Felodipine is a calcium channel blocker. It works by relaxing and widening your blood vessels. This makes it easier for blood to flow, which lowers blood pressure.

Common Side Effects
diltiazem
  • Swelling in your ankles or feet
  • Headache
  • Dizziness
  • Slow heart rate
  • Constipation
felodipine
  • Swelling in your ankles or feet
  • Headache
  • Flushing (redness of face)
  • Feeling tired
FAERS Reports
diltiazem
  • Shortness of breath 3,200
  • Tiredness 2,637
  • Feeling sick to your stomach 2,372
  • Discomfort 2,364
  • Feeling lightheaded 2,089
felodipine
  • Feeling tired 1,050
  • Difficulty breathing 953
  • Feeling lightheaded 946
  • Loose stools 846
  • Feeling sick to your stomach 846
Serious Warnings
diltiazem

Diltiazem can interact with other heart medications. Tell your doctor if you take beta-blockers or digoxin. Using diltiazem with these drugs can cause heart problems. Your doctor may need to adjust your dosages.

felodipine

If you take certain medicines like ketoconazole, itraconazole, or erythromycin, talk to your doctor. These drugs can greatly increase the amount of felodipine in your blood, leading to unwanted effects. Also, if you take anticonvulsants like phenytoin, carbamazepine, or phenobarbital, felodipine may not work as well.

Pregnancy
diltiazem

Tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. It is not known if diltiazem will harm your unborn baby. Diltiazem passes into breast milk, so talk to your doctor about breastfeeding while taking this medicine.

felodipine

Tell your doctor if you are pregnant or plan to become pregnant. It is not known if felodipine will harm your unborn baby. Talk to your doctor about breastfeeding while taking felodipine.

Also Compare — Nearby Drugs

How to Read This diltiazem vs felodipine Comparison

diltiazem is classified in the Calcium Channel Blocker drug class, while felodipine 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, diltiazem has 12,662 submissions while felodipine has 4,641. 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 substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between diltiazem and felodipine — always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.