Last reviewed 2026-04-22 · How we verify

Amoxicillin Short

Amoxicillin inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins and blocking peptidoglycan cross-linking.

Amoxicillin inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins and blocking peptidoglycan cross-linking. Used for Bacterial infections including otitis media, sinusitis, respiratory tract infections, urinary tract infections, and skin infections, Helicobacter pylori eradication (as part of combination therapy).

At a glance

Mechanism of action

Amoxicillin is a beta-lactam antibiotic that penetrates bacterial cell walls and irreversibly binds to penicillin-binding proteins, preventing the cross-linking of peptidoglycan strands. This disrupts cell wall integrity, leading to bacterial cell lysis and death. It is bactericidal and effective against a broad spectrum of gram-positive and some gram-negative bacteria.

Approved indications

• Bacterial infections including otitis media, sinusitis, respiratory tract infections, urinary tract infections, and skin infections
• Helicobacter pylori eradication (as part of combination therapy)

Common side effects

• Diarrhea
• Nausea
• Rash
• Allergic reaction / anaphylaxis
• Vomiting

Key clinical trials

• Fast Track Therapeutic Model in Acute Complicated Appendicitis in Pediatrics (PHASE4)
• Testing a Novel Combination Treatment (Arm D) Versus Standard of Care for Intensive Phase Treatment for Mycobacterium Abscessus Pulmonary Disease in People With or Without Cystic Fibrosis in the Finding the Optimal Regimen for Mycobacterium Abscessus Treatment (FORMaT) Adaptive Platform Trial (PHASE2)
• Short Versus Standard of Care Antibiotic Duration for Children Hospitalized for CAP (PHASE4)
• 7-day High-Dose Vonoprazan-amoxicillin Dual Therapy Versus 14-day Vonoprazan-amoxicillin Dual Therapy for H. Pylori (NA)
• Antibiotic Prophylaxis After Simple Tooth Extraction in Immunosuppressed Patients With Autoimmune Rheumatic Diseases (PHASE4)
• Comparing Short to Standard Amoxicillin Course for Erysipelas (PHASE4)
• Epidemiology of Antimicrobial-use and Antimicrobial-resistant Infections in Four Hospitals in Thailand
• Penicillin Allergy Delabeling After a One-Dose Versus Two-Dose Graded Direct Oral Challenge (PHASE3)

Primary sources

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