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Lansoprazole and Clarithromycin Interaction

Drug interaction information between Lansoprazole and Clarithromycin.

Lansoprazole and Clarithromycin have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Lansoprazole and Clarithromycin. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.

Drug A

Lansoprazole

Proton Pump Inhibitor (PPI)

Drug B

Clarithromycin

Macrolide Antibiotic

How They Interact

Clarithromycin can cause serious and potentially fatal heart rhythm problems when combined with certain other drugs.

What To Do

Your doctor must check for heart risks before you take these medicines together.

FDA Label Information

Combination Therapy with Clarithromycin and Amoxicillin Clinical Impact: Concomitant administration of clarithromycin with other drugs can lead to serious adverse reactions, including potentially fatal arrhythmias, and are contraindicated. Intervention : See Contraindications and Warnings and Precautions in prescribing information for clarithromycin.

Frequently Asked Questions

Can I take Lansoprazole and Clarithromycin together?

This is a major interaction. Your doctor must check for heart risks before you take these medicines together.

How serious is the interaction between Lansoprazole and Clarithromycin?

This interaction is classified as "major" severity by the FDA. Major interactions may be life-threatening or cause serious side effects.

Why do Lansoprazole and Clarithromycin interact?

Clarithromycin can cause serious and potentially fatal heart rhythm problems when combined with certain other drugs.

Understanding the Lansoprazole and Clarithromycin Interaction

FDA-approved prescribing information for these two drugs flags their combination as a major-severity interaction. Lansoprazole belongs to the Proton Pump Inhibitor (PPI) class and Clarithromycin belongs to the Macrolide Antibiotic class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Clarithromycin can cause serious and potentially fatal heart rhythm problems when combined with certain other drugs. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.

Context around a specific patient determines real-world impact. Lansoprazole has 14 total documented interactions on file in this dataset, and Clarithromycin has 81. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Your doctor must check for heart risks before you take these medicines together. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.

An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Lansoprazole or Clarithromycin based on a web page, speak with your prescriber or pharmacist before making any change.

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.