PrescriptionDrugs.org

Penicillin Antibiotics

Medical Disclaimer: This content is for informational purposes only and does not constitute medical advice. Always consult your healthcare provider before starting, stopping, or changing any medication. Using this site does not create a doctor-patient relationship.

Drug information changes as the FDA updates labeling, and we cannot guarantee it is complete or current. Verify critical details with your pharmacist or physician.

Emergencies: If you think you may have a medical emergency, call 911 immediately. For a suspected overdose, call Poison Control at 1-800-222-1222. Report side effects to the FDA MedWatch program at fda.gov/medwatch or 1-800-FDA-1088.

See our Terms of Use and Editorial Policy.

Overview

Penicillin antibiotics are a group of bactericidal drugs that kill bacteria by disrupting cell wall synthesis. They are among the most widely prescribed antibiotics worldwide.

How do penicillin antibiotics work?

Penicillins bind to penicillin-binding proteins (PBPs) in the bacterial cell wall, inhibiting transpeptidation and preventing cross-linking of peptidoglycan chains. This weakens the cell wall, leading to cell lysis and death.

Drugs in this class

Frequently asked questions