Abstract
Fluorouracil (FU), or 5-FU, is an antimetabolite, pyrimide analog with thymidylate synthase as its target, which alters DNA replication. It is available in 250-mg doses for systemic use, and is administered intravenously or orally as adjuvant chemotherapy in cancer treatment. Currently, 5% 5-FU cream is applied twice daily for 2–4 weeks for superficial actinic keratoses treatment. It is approved for superficial basal cell carcinoma when conventional methods are impractical, such as in cases of multiple lesions or difficult treatment sites. Despite high efficacy, irritation limits adherence. Alternatives for better tolerability are low-concentration creams (0.5, 1 and 2%) or superficial peels, with 5% 5-FU in propylenoglycol, weekly or biweekly, until the desired end point is reached. Off-label topical uses include the following: Bowen’s disease, warts, extramammary Paget’s disease, Darier’s disease, linear verrucous epidermal nevus, porokeratosis and chromoblastomycosis. Intralesional 5-FU is also used for treatment of keloids and hypertrophic scars. Studies comparing 5% 5-FU cream to new options for the treatment of actinic keratoses, such as 0.5% 5-FU cream, photodynamic therapy, 5% imiquimod cream and 3% diclofenac gel, demonstrated similar efficacy. All the listed 5-FU options have skin irritation as a side effect and low cost as a considerable advantage.
Financial & competing interest disclosure
The author has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. Reviewers writing assistance provided by Valeant Pharmaceuticals was utilized in the production of this manuscript.
Notes
Efudix, Efudex and Efurix are registered trademarks of Valeant Pharmaceuticals International (CA, USA) or its subsidiary and affiliated companies.
5-FU: 5-fluorouracil; AK: Actinic keratoses; BCC: Basal cell carcinoma; HPV: Human papillomavirus.
