Does topical 5-fluorouracil treat actinic keratosis?

Actinic keratosis is a sun-damaged area of rough, scaly skin. Topical 5-fluorouracil acts on abnormal cells in the treated field. Redness, tenderness, scaling, and crusting can develop as the medicine produces an inflammatory response. The reaction may be more noticeable where there are several sun-damaged spots close together.

The cream is not suitable for every lesion. A thick, tender, bleeding, or rapidly changing spot may need closer examination or a biopsy because its depth or diagnosis could alter treatment. The clinician also considers the body site, number of areas, skin sensitivity, and previous treatment.

Apply the cream exactly as directed to the prescribed area, and wash your hands afterwards. Protect the skin from sunlight and avoid picking, scrubbing, or adding other active products unless your clinician approves them. Keep a note of severe discomfort or unexpected changes so the treatment plan can be adjusted safely.

More detail about this medicine is available in [Topical 5-Fluorouracil](/treatments/medical-dermatology/topical-5-fluorouracil/). Arrange the planned follow-up even if the surface looks improved, because the treated field still needs assessment.

Tell the prescribing clinician if swelling, blistering, extensive weeping, or pain interferes with normal activities. Seek prompt review for a spot that becomes thick, increasingly painful, ulcerated, or prone to bleeding, or for a lesion that does not respond as expected. Eye exposure requires urgent advice and careful rinsing according to medical guidance.

Which lesions or skin field should I treat, and for how long? What degree of redness or crusting is expected for my plan? Which cleanser, moisturiser, or dressing can I use during the reaction? How will you check the area afterwards, and what would require another procedure?