Ampicillin

Name: Ampicillin Drug Interactions
Creator: Dr. Brian Staiger, PharmD, BCPS

72 interactions 1 explained in plain English 590 cited references

Also sold as: Amcill® Omnipen® Penbritin® Pfizerpen® Polycillin® Polyflex Principen® Totacillin®

About Ampicillin

Ampicillin is a penicillin antibiotic used to treat bacterial infections including meningitis, throat, sinus, lung, and urinary tract infections. Read the full Ampicillin drug information page →

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Jul 12, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Amifampridine Bupropion Chlortetracycline Cholera Vaccine, Live Minocycline Topical Levonorgestrel Intrauterine System

44 Major 12 Moderate 16 Minor

All (72) Major (44) Moderate (12) Minor (16)

Major

Ampicillin Exenatide Injection Bydureon Reduced oral antibiotics absorption and reduced efficacy of oral antibiotics Details Ampicillin Levonorgestrel Intrauterine System Kyleena Decreased contraceptive effectiveness Details Ampicillin Methotrexate Injection Abitrexate® Increased methotrexate exposure, an increased risk of methotrexate-related severe adverse reactions, reduced active metabolite for... Details Ampicillin Minocycline Topical Amzeeq Decreased antibacterial effectiveness Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.