This experiment was performed to determine whether the dosages of penicillin G potassium currently in clinical use have the potential to interfere with wound healing. In this aim we have fallen short in two respects: (1) data on healing in rats cannot be rigidly applied to humans; and (2) the medication was given in two large doses rather than continuously as in clinical practice. However, the lack of any evidence of interference with wound strength, even after doses corresponding to 80 million units/day in a man weighing 70 kg (154 lb), suggests strongly that currently used penicillin G potassium dose schedules do not constitute a risk to wound healing.
Richard Pohl, Thomas K. Hunt. Penicillin G and Wound Healing. Arch Surg. 1970;101(5):610–611. doi:10.1001/archsurg.1970.01340290066014