Topical 5-Fluorouracil

Topical 5-fluorouracil is a prescription medicine applied to the skin. It interferes with the growth of rapidly dividing abnormal cells near the surface. A dermatologist may use it for actinic keratoses, actinic cheilitis, or selected superficial lesions such as Bowen's disease. The treatment plan depends on the body site, the number of visible areas, and what examination or biopsy shows.

Topical 5-fluorouracil is a prescription cream that treats selected abnormal, sun-damaged surface skin cells.

The cream itself is usually easy to apply, but treated skin commonly becomes red, dry, scaly, tender, or stinging as abnormal cells respond. The reaction can look more noticeable before it settles. Do not cover the area or add soothing products unless your prescriber has advised it, because dressings and extra products can change how much medicine reaches the skin.

A dermatologist can use topical 5-fluorouracil safely when the diagnosis, application area, and schedule are clear. Keep it away from the eyes, lips, inside of the nose, and broken skin unless specifically directed. Tell the prescriber about pregnancy, breastfeeding, medicines, allergies, and any immune or blood condition before starting. Seek medical advice for severe swelling, blistering, spreading pain, or an unexpected reaction.

The treated area may remain clearer after the course ends, but new sun damage can develop later. Results therefore depend on ongoing sun protection, skin checks, and whether every abnormal area has been identified. A follow-up visit lets the dermatologist assess healing and decide whether another approach is needed.

This is a field treatment: it can address visible and less obvious abnormal cells within the prescribed area. It is not a general moisturiser or a cream to use on undiagnosed spots. Use only the amount and frequency prescribed, wash hands after application, and protect treated skin from sunlight.

A dermatologist may recommend it when examination supports a superficial sun-related skin change and a field of skin needs treatment. It may be considered for [Actinic Keratosis](/conditions/actinic-keratosis/), [Actinic Cheilitis](/conditions/actinic-cheilitis/), or selected [Bowen's Disease](/conditions/bowens-disease/). A changing, bleeding, thickened, or non-healing spot may need assessment rather than self-treatment.

Your clinician identifies the treatment field and explains the schedule. You apply a thin layer to clean, dry skin exactly as directed, avoiding unintended areas. The skin response is monitored through planned follow-up. Once the prescribed course is complete, stop as instructed and continue the recommended aftercare.

Redness and scaling may continue during the treatment reaction and early healing. Keep the area clean, avoid picking or rubbing, and use the aftercare recommended for that site. Sun protection matters because treated skin is sensitive. Contact the clinic if discomfort prevents normal activities or the reaction seems disproportionate.

Possible problems include irritation, crusting, inflammation, soreness, pigment change, infection, or a reaction extending beyond the intended area. The cream may be unsuitable for some lesions or locations. A persistent or changing area after treatment needs review, since treatment response alone does not replace diagnosis.

Depending on the diagnosis, site, and extent of disease, options may include freezing, curettage, excision, or [Photodynamic Therapy](/treatments/laser-and-energy/photodynamic-therapy/). Your dermatologist can explain why one option may fit a particular lesion and whether tissue sampling is needed.

Choose a dermatologist who can confirm the diagnosis, explain the application schedule, and arrange follow-up. Bring a list of medicines and products used on the area, and mention previous reactions to skin treatments. Ask how to protect nearby skin and which changes should prompt a call.