Penicillin V (Phenoxymethylpenicillin) is an antibiotic in the Penicillin family. Penicillin V is used to treat many different types of bacterial infections. This antibiotic is primarily active against gram-positive bacteria, which includes the acne-causing Propionibacterium acnes bacterium.
Penicillin V is available in topical and oral formulations. Penicillin V is occasionally used as an oral antibiotic for the treatment of acne. For topical use, the closely-related Penicillin G is more commonly prescribed.
Penicillin V and Penicillin G are notable because they consistently score very well in laboratory testing of antibiotic susceptibility of the P. acnes bacterium. These antibiotics kill P. acnes bacteria at very low concentrations, and Penicillin-resistant P. acnes bacteria are very uncommon.
Clinical research and patient reports have indicated that oral treatment with Penicillin family antibiotics (eg. Amoxicillin, Ampicillin, Penicillin V) is effective at improving acne symptoms for many patients. The topical use of Penicillin also appears to be a useful acne treatment.