Efudex (5-fluorouracil) has been used as topical chemotherapy for the treatment of actinic keratoses (AKs) since the 1950's. Through many years of use, Efudex has been deemed to be a safe and effective therapy. It requires, however, a high level of patient compliance and is known to cause a vigorous inflammatory reaction when actinic keratoses are treated. It has the distinct advantage of identifying precancerous skin lesions not apparent on clinical inspection or palpation. Following a course of Efudex to the face, patients have been noted to have fewer signs of dermatoheliosis.