Does topical 5-fluorouracil treat actinic cheilitis?

Actinic cheilitis is sun-related damage affecting the lip, often the lower lip. The cream acts on abnormal, sun-damaged cells at the treated surface. During a course, the lip may become red, sore, crusted, or irritated as the medicine acts. The visible reaction varies with the area treated and the condition of the lip.

A clinician needs to confirm that the lip change is suitable for a cream. A persistent thickened area, ulcer, bleeding spot, or firm lump may need a different assessment or a sample before treatment. Treatment choice also depends on the size, thickness, location, and previous care of the affected area.

Use the prescribed amount and schedule, applying it only to the instructed lip area. Wash your hands after application and protect the treated lip from sun, wind, and irritating products. Do not pick crusts or increase applications because the reaction seems mild. Your clinician may advise pauses, soothing care, or a review during the course.

The [Topical 5-Fluorouracil](/treatments/medical-dermatology/topical-5-fluorouracil/) page explains the treatment more broadly. Keep follow-up appointments so the lip can be checked after the visible reaction settles.

Contact the prescribing clinic if swelling, pain, cracking, or inflammation makes eating or drinking difficult, or if the reaction extends beyond the instructed area. Seek prompt assessment for a new ulcer, bleeding, rapid thickening, a persistent lump, or a change that does not settle after treatment. These findings need direct examination rather than self-treatment.

Is the lip change suitable for topical 5-fluorouracil, or does it need sampling first? Which areas should receive the cream, and what reaction should I expect? What should I apply if the lip becomes cracked or uncomfortable? When will you check whether the treated area has cleared?