famotidine vs warfarin
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Side-by-side comparison of famotidine and warfarin. 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
Table 2: Examples of CYP450 Interactions with Warfarin Enzyme Inhibitors Inducers CYP2C9 amiodarone, capecitabine, cotrimoxazole, etravirine, fluconazole, fluvastatin, fluvoxamine, metronidazole, miconazole, oxandrolone, sulfinpyrazone, tigecycline, voriconazole, zafirlukast aprepitant, bosentan, carbamazepine, phenobarbital, rifampin CYP1A2 acyclovir, allopurinol, caffeine, cimetidine, ciprofloxacin, disulfiram, enoxacin, famotidine, fluvoxamine, methoxsalen, mexiletine, norfloxacin, oral contraceptives, phenylpropanolamine, propafenone, propranolol, terbinafine, thiabendazole,...
Pepcid
Coumadin, Jantoven
Famotidine (Pepcid) reduces stomach acid. It is used to treat ulcers, heartburn, and acid reflux.
Warfarin is a medicine that helps prevent blood clots. It is used to treat and prevent dangerous clots from forming in your body.
This medicine treats active duodenal ulcers and active gastric ulcers. It also treats heartburn (nonerosive GERD) and erosive esophagitis (damage to the esophagus from acid reflux). Famotidine can also treat conditions where the stomach makes too much acid, like Zollinger-Ellison syndrome. It can also lower the risk of duodenal ulcers coming back.
Warfarin is used to prevent and treat blood clots in your veins and lungs. It can also prevent clots if you have atrial fibrillation (irregular heartbeat) or a replacement heart valve. After a heart attack, it can lower the risk of death, another heart attack, or a stroke.
Famotidine is an H2 receptor antagonist. This means it blocks histamine, a substance that tells your stomach to make acid. By blocking histamine, famotidine reduces the amount of acid your stomach produces.
Warfarin works by blocking your body's use of vitamin K. Vitamin K is needed to make blood clotting factors. By blocking vitamin K, warfarin makes your blood less likely to clot.
- • Headache
- • Dizziness
- • Constipation
- • Diarrhea
- • Bleeding from any tissue or organ
- Nausea 7,258
- Fatigue 6,866
- Chronic Kidney Disease 6,644
- Diarrhoea 6,452
- Dyspnoea 5,202
- International Normalised Ratio Increased 10,276
- Dyspnoea 8,408
- Drug Interaction 6,288
- Fatigue 6,143
- Nausea 5,921
In elderly patients and those with kidney problems, famotidine can cause confusion, delirium, or hallucinations. If you are elderly or have kidney problems, your doctor may prescribe a lower dose. Famotidine can hide the symptoms of stomach cancer. If your symptoms don't improve, tell your doctor.
Warfarin can cause major or fatal bleeding. You must have your blood tested regularly (INR) while taking warfarin. Many things, like other medicines and diet changes, can affect your INR. Tell your doctor about any bleeding and follow their instructions to prevent bleeding.
It is not known if famotidine will harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. Famotidine may pass into breast milk, but it's not expected to harm the baby. Talk to your doctor about breastfeeding while taking this medicine.
Warfarin can harm your unborn baby, especially during the first three months of pregnancy. Do not take warfarin if you are pregnant, unless you have a mechanical heart valve and your doctor says the benefits outweigh the risks. Talk to your doctor if you are breastfeeding, and watch your baby for bruising or bleeding.
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How to Read This famotidine vs warfarin Comparison
famotidine is classified in the H2 Receptor Antagonist drug class, while warfarin sits within the Vitamin K Antagonist (Anticoagulant) 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, famotidine has 32,422 submissions while warfarin has 37,036. 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 famotidine slows down the liver enzymes that break down warfarin. this can cause warfarin to build up in your blood, making it more likely for you to bleed.. 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 famotidine or warfarin.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.