Penicillin for Treating Infections in Cystic Fibrosis

Penicillin was first used in the early 1940s, one of the first groups of antibiotics available to fight infection in people. There are different types of penicillins, but all share characteristics. An important point here is that anyone allergic to one penicillin is likely to be allergic to all types of penicillin, and penicillin allergies are a known problem with CF patients.

People with cystic fibrosis (CF) usually develop bacterial infections due to the buildup of thick, sticky mucus in their lungs, and penicillins are a potential choice of treatment.

History of penicillin

Penicillin was discovered in September 1928 by Alexander Fleming, when he returned to his London home from a vacation and found that a mold, called Penicillium notatum, had contaminated one of the Petri dishes where colonies of Staphylococcus bacteria were growing. On examining the fungi, he realized the mold had prevented the bacteria’s growth. Further study led him to conclude that the mold — which he called “mold juice” — also might be way of  combating infectious diseases. Work by scientists at Oxford eventually turned penicillin into an effective antibiotic.

In February 1941, a policeman, Albert Alexander, became the first person treated with the Oxford penicillin.

How penicillin works

Penicillin works by acting on the bacterial cell walls. These cell walls have peptidoglycans, enzymes which largely work to keep external fluids — like water — from entering. By weakening bacterial cell walls, the antibiotic opens breaches in those walls that subject the cells to what is known as osmotic pressure, or differences in internal and external pressure forces, that cause the cells to rupture and die.

Penicillin, a bactericidal, directly kills the bacteria.

More about penicillin & CF

Penicillin, a narrow-spectrum antibiotic, treats infections caused by Staphylococcus aureus and Pseudomonas aeruginosa, the major bacterial infection in CF. The antibiotic can be taken as a tablet, intravenously, or intramuscularly. It takes about 48 hours to be effective.

Side effects associated with penicillin can include nausea and vomiting, blurred vision, dizziness and tiredness. Some people may be allergic to penicillin. Emergency medical help should be sought if any signs of allergic reaction appear: hives, difficulty breathing, or swelling of the face, lips, tongue, or throat.

Amoxicillin and clavulanic acid (brand name, Augmentin), cloxacillin and dicloxacillin, ticarcillin and clavulanate (brand name Timentin) are used for Staphylococcus aureus infections. Methicillin, oxacillin and nafcillin, cabenicillin, ticarcillin, piperacillin, mezlocillin, azlocillin, piperacillin and tazobactam (brand name, Zosyn) are used for Pseudomonas aeruginosa infections.1

Cystic Fibrosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

Your CF Community


Visit the Cystic Fibrosis News Today forums to connect with others in the CF community.