Abstract
The effect of topically applied 5-fluorouracil on epithelialization of shallow wounds was studied. The drug delayed epithelialization of wounds in each of 11 subjects compared to the control ointments. In no case did the drug alter normal intact skin. Counts of mitoses in the epidermis at wound margins revealed a significant inhibition of mitosis associated with 5-fluorouracil treatment. It is proposed that the specific effect of 5-fluorouracil on cutaneous neoplastic lesions is related to selectively greater absorption of the agent in diseased skin compared to adjacent normal skin.