Penicillin V potassium comes as a tablet and as an oral solution (liquid) to take by mouth. For the treatment of infections, it is usually taken every 6 hours (four times a day) or every 8 hours (three times a day). For the prevention of rheumatic fever, it is usually taken twice a day.

The introduction of penicillin in the 1940s, which began the era of antibiotics, has been recognized as one of the greatest advances in therapeutic medicine.