Fluorouracil (flure oh yoor' a sill) is a drug that is used to treat actinic keratoses. This is a pre-cancerous skin growth caused by the sun. Fluorouracil reacts against the pre-cancerous sun-damaged skin but does not usually affect normal skin.

What does efudex do to healthy skin?

Efudix contains the active ingredient fluorouracil and belongs to a group of medicines called anti-cancer medicines (also called antineoplastic or cytotoxic medicines) that are applied to the skin. It works by destroying precancerous and cancerous cells, while having little effect on normal cells.

Does Efudix affect normal skin?

4.2 Dose and Method of Administration

Efudix should only be used under medical supervision. Efudix is well tolerated. The healthy skin surrounding the area being treated may occasionally become reddened, but soon resumes its normal colour on cessation of treatment.