amiodarone vs cimetidine

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Side-by-side comparison of amiodarone and cimetidine. 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

Pharmacokinetic Interactions CYP450 Inhibitors grapefruit juice, certain fluoroquinolone and macrolide antibiotics, azole antifungals, cimetidine, certain protease inhibitors Increased exposure of amiodarone.

Drug Class
amiodarone Class III Antiarrhythmic
cimetidine H2 Receptor Antagonist
Type
amiodarone Prescription
cimetidine Over-the-Counter
Summary
amiodarone

Amiodarone (Pacerone) is a medicine used to treat life-threatening, irregular heartbeats. It helps to restore a normal heart rhythm when other medicines don't work or can't be used.

cimetidine

Cimetidine (Tagamet) reduces stomach acid. It is used to treat ulcers, heartburn, and other conditions where too much acid is produced.

What It Treats
amiodarone

This medicine treats very fast, irregular heartbeats in the ventricles (lower chambers of the heart). It is used when these irregular heartbeats are life-threatening. It is also used when other medicines don't work well enough or cause too many side effects. This medicine is for adults.

cimetidine

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.

How It Works
amiodarone

Amiodarone affects the electrical signals in your heart. It slows down these signals, which helps your heart beat normally. This medicine can help prevent dangerous, fast heart rhythms.

cimetidine

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.

Common Side Effects
amiodarone
  • Low thyroid levels (hypothyroidism)
  • High thyroid levels (hyperthyroidism)
  • Heart failure
  • Irregular heartbeats
  • Problems with the heart's natural pacemaker (SA node dysfunction)
cimetidine
  • Headache
  • Dizziness
  • Diarrhea
FAERS Reports
amiodarone
  • Dyspnoea 1,158
  • Asthenia 975
  • Fatigue 895
  • Nausea 606
  • Cough 597
cimetidine
  • Chronic Kidney Disease 1,264
  • Acute Kidney Injury 710
  • Renal Failure 694
  • Nausea 681
  • Fatigue 598
Serious Warnings
amiodarone

This medicine can cause serious problems with your lungs, liver, and heart. Lung problems can be fatal. Your doctor will check your lungs with X-rays and breathing tests. Liver problems can also be fatal. Your doctor will check your liver with blood tests. This medicine can also make irregular heartbeats worse. You will likely start this medicine in the hospital where your heart can be monitored.

cimetidine

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.

Pregnancy
amiodarone

This medicine can harm your unborn baby. It can cause thyroid problems, slow heart rate, and brain development issues. Do not breastfeed while taking this medicine.

cimetidine

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.

Also Compare, Nearby Drugs

How to Read This amiodarone vs cimetidine Comparison

amiodarone is classified in the Class III Antiarrhythmic drug class, while cimetidine sits within the H2 Receptor Antagonist 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, amiodarone has 4,231 submissions while cimetidine has 3,947. 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 blocks the enzymes that break down amiodarone in your body. this causes the levels of amiodarone in your blood to rise, which could increase the risk of side effects.. 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 amiodarone or cimetidine.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.