Lansoprazole and Amoxicillin Interaction
Drug interaction information between Lansoprazole and Amoxicillin.
Lansoprazole and Amoxicillin have a documented major interaction in FDA labeling.
FDA drug labeling documents a major-severity interaction between Lansoprazole and Amoxicillin. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Using these drugs together as part of a treatment plan can increase the risk of side effects or change how other medicines work.
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. Amoxicillin also has drug interactions. See Drug Interactions in prescribing information for amoxicillin.
Lansoprazole Also Interacts With
- Clarithromycin major
- Rifampin moderate
- Tacrolimus Topical moderate
- Warfarin minor
- Methotrexate minor
Amoxicillin Also Interacts With
- Rabeprazole major
- Theophylline major
- Allopurinol moderate
- Probenecid moderate
- Estradiol minor
Frequently Asked Questions
What SPL severity band is on file for Lansoprazole + Amoxicillin?
Compiled FDA labeling labels this pair major. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Lansoprazole has 14 labeled pairs on file vs Amoxicillin's 12. In the major band specifically: Lansoprazole has 2 (also Clarithromycin); Amoxicillin has 3 (also Rabeprazole, Theophylline).
What mechanism field is on file for Lansoprazole and Amoxicillin?
Using these drugs together as part of a treatment plan can increase the risk of side effects or change how other medicines work.
Amoxicillin carries more major-labeled pairs than Lansoprazole
SPL source-record counts only. This page's band is major · classes on file: Lansoprazole (Proton Pump Inhibitor (PPI)); Amoxicillin (Penicillin Antibiotic).
Amoxicillin has 3 major-labeled pairs vs Lansoprazole's 2.
2 major · 2 moderate · 10 minor · 14 total
- Other major peers for Lansoprazole
- Clarithromycin
3 major · 2 moderate · 7 minor · 12 total
- Other major peers for Amoxicillin
- Rabeprazole
- Theophylline
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.