C. diff Risk


Oral Bioavailability


Approximate Cost


500-1000mg PO TID

General Information

Common Usage

Amoxicillin is used in the treatment of infections due to certain Streptococcus spp. and Enterococcus spp. as well as treatment of infections due to susceptible Gram negative infections.

Commonly used for upper respiratory tract infections and urinary tract infections.

Adverse Effects

  • Allergic reactions, rash

  • Cytopenias

  • Clostridium difficile associated diarrhea

Major Interactions

Allopurinol - increased frequency of rash

Additional Information

Patients with infectious mononucleosis secondary to EBV and given amoxicillin or ampicillin may develop a rash and this is not indicative of a true allergy.


Antimicrobial class: Aminopenicillin

Pregnancy category: B

Average serum half life: 1 hour

Biliary penetration: Therapeutic

CSF penetration: Moderate

Lung penetration: Therapeutic

Urine penetration: Therapeutic