Penicillin (Antibiotics)

  • Pharmacy Author:
    Omudhome Ogbru, PharmD

    Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

  • Medical and Pharmacy Editor: Jay W. Marks, MD
    Jay W. Marks, MD

    Jay W. Marks, MD

    Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

What drugs interact with penicillin antibiotics?

Penicillin antibiotics have few important drug interactions.

  • Probenecid (Benemid) causes an increase in the amount of penicillins in the body by preventing excretion of penicillin by the kidneys.
  • Combining ampicillin with allopurinol (Zyloprim) can increase the incidence of drug-related skin rash.
  • Penicillin antibiotics may reduce the effect of BCG live vaccine and typhoid live vaccine.

What formulations of penicillin antibiotics are available?

Penicillin antibiotics are available as

  • tablets,
  • capsules,
  • powder for oral suspension, and
  • powder for injection.

Are penicillin antibiotics safe to take during pregnancy or while breastfeeding?

  • Penicillin antibiotics are considered safe to use during pregnancy.
  • Although small amounts of penicillins pass into breast milk they are considered safe to use while breastfeeding.

How do penicillin antibiotics work?

Penicillin antibiotics stop bacteria from multiplying by preventing bacteria from forming the walls that surround them. The walls are necessary to protect the bacteria from their environment, and to keep the contents of the bacterial cell together. Bacteria cannot survive without a cell wall. Penicillin antibiotics are most effective when bacteria are actively multiplying and forming cell walls.

REFERENCE: FDA Prescribing Information

Medically Reviewed by a Doctor on 12/9/2016
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