cimetidine vs metformin
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Side-by-side comparison of cimetidine and metformin. 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
Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine. ( 7 ) Drugs that reduce metformin clearance (such as ranolazine, vandetanib, dolutegravir, and cimetidine) may increase the accumulation of metformin.
Tagamet
Glucophage, Fortamet, Glumetza
Cimetidine (Tagamet) reduces stomach acid. It is used to treat ulcers, heartburn, and other conditions where too much acid is produced.
No summary available.
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.
Information not available.
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.
Information not available.
- • Headache
- • Dizziness
- • Diarrhea
- • Diarrhea
- • Upper respiratory tract infection (like a cold)
- • Headache
- Chronic Kidney Disease 1,264
- Acute Kidney Injury 710
- Renal Failure 694
- Nausea 681
- Fatigue 598
- Nausea 21,946
- Diarrhoea 21,884
- Blood Glucose Increased 18,328
- Fatigue 17,252
- Acute Kidney Injury 16,440
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.
No specific warnings noted.
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.
No pregnancy information available.
Also Compare, Nearby Drugs
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How to Read This cimetidine vs metformin Comparison
cimetidine is classified in the H2 Receptor Antagonist drug class, while metformin sits within the Biguanide 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 metformin has 95,850. 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 prevents your body from getting rid of metformin normally, which can lead to higher levels of the drug in your system.. 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 metformin.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.