What to expect from topical 5-fluorouracil for actinic keratosis

The medicine disrupts abnormal sun-damaged cells in the area selected by your clinician. As those cells respond, the skin can look more inflamed before it settles. The strength, application schedule, and treatment area vary, so do not copy someone else’s instructions. A treated patch may improve while a separate rough or bleeding spot still needs examination.

Apply the prescribed amount to clean, dry skin and wash your hands afterwards. Avoid eyes, lips, broken skin, and unnecessary contact with other people until the medicine has been absorbed or removed as instructed. Do not pick crusts or cover the area with an unapproved dressing. Use gentle cleansing and the recommended moisturiser or sun protection. Keep a note of new symptoms and attend the planned review, especially if the treated area is on the face, scalp, or hands where irritation affects daily activities.

Ask the clinic for advice if pain, swelling, blistering, or irritation makes normal activities difficult, or if the reaction extends well beyond the application area. Seek urgent help for breathing difficulty or sudden widespread swelling. A thickened, tender, ulcerated, or bleeding lesion that persists after healing needs review because not every rough spot is necessarily an actinic keratosis.

Which lesions should receive the medicine, and how will I know where the treatment ends? What reaction is expected for my schedule? What can I use for comfort, when should I stop or pause, and when should a persistent lesion be checked again?