cimetidine vs propafenone
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Side-by-side comparison of cimetidine and propafenone. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
minor Known Drug Interaction
Cimetidine Concomitant administration of propafenone immediate-release tablets and cimetidine in 12 healthy subjects resulted in a 20% increase in steady-state plasma concentrations of propafenone.
Tagamet
Rythmol
Cimetidine (Tagamet) reduces stomach acid. It is used to treat ulcers, heartburn, and other conditions where too much acid is produced.
Propafenone (Rythmol) is a medicine that helps control irregular heartbeats. It works by slowing down electrical signals in the heart.
Cimetidine treats active duodenal ulcers for short periods. It can also be used long-term at a lower dose to prevent ulcers from returning. This medicine also treats active benign gastric ulcers for a short time. Additionally, it can help with erosive gastroesophageal reflux disease (GERD), which damages the esophagus.
This medicine is used to help keep your heart rhythm normal if you have atrial fibrillation or supraventricular tachycardia. These are types of fast or irregular heartbeats that can cause problems. It can also treat life-threatening ventricular arrhythmias. Propafenone is for people without structural heart disease.
Cimetidine is an H2 receptor antagonist. This means it blocks histamine from attaching to certain cells in your stomach. By blocking histamine, cimetidine reduces the amount of acid your stomach makes.
Propafenone works by affecting the electrical activity in your heart. It slows down the signals that cause irregular heartbeats. This helps your heart beat more regularly.
- • Headache
- • Dizziness
- • Diarrhea
- • Unusual taste
- • Nausea
- • Vomiting
- • Dizziness
- • Constipation
- Chronic Kidney Disease 1,264
- Acute Kidney Injury 710
- Renal Failure 694
- Nausea 681
- Fatigue 598
- Atrial Fibrillation 347
- Drug Interaction 320
- Dizziness 262
- Toxicity To Various Agents 231
- Dyspnoea 226
Reversible confusional states (like mental confusion, agitation, or hallucinations) have been reported, mostly in severely ill patients. These usually appear within 2-3 days of starting treatment and clear up within 3-4 days of stopping the drug.
This medicine may increase the risk of death in people with heart problems. Do not take this medicine if you have structural heart disease and non-life-threatening ventricular arrhythmias. Talk to your doctor about the risks and benefits of taking this medicine.
Tell your doctor if you are pregnant or plan to become pregnant. The effects of cimetidine during pregnancy are not fully known. Talk to your doctor about the risks and benefits of taking cimetidine while breastfeeding.
Tell your doctor if you are pregnant or plan to become pregnant. This medicine can cross the placenta, and may affect the baby. Your doctor will monitor you and your baby for any problems.
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How to Read This cimetidine vs propafenone Comparison
cimetidine is classified in the H2 Receptor Antagonist drug class, while propafenone sits within the Class IC Antiarrhythmic class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are split between OTC and prescription status, which affects access and supervision.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, cimetidine has 3,947 submissions while propafenone has 1,386. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to cimetidine changes how your body handles propafenone, which can cause the levels of propafenone in your blood to rise.. 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 cimetidine or propafenone.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.