Fluorouracil
Efudex is a topical chemotherapy medication containing fluorouracil (5-FU) that is primarily prescribed for treating actinic keratosis (precancerous skin growths caused by sun damage) and certain superficial skin cancers. The medication works by inhibiting the growth of abnormal cells in the skin, causing affected areas to become red, inflamed, and eventually crust over before clearing.
Efudex is a topical cancer medication used to treat precancerous skin lesions and certain superficial skin cancers by inhibiting abnormal cell growth.
Key facts at a glance
- RxNorm
- 224945
- Generic
- Efudex
- Class
- brand-name
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Efudex is used to treat actinic keratosis (precancerous skin lesions) and superficial basal cell carcinoma on the skin. It is typically applied to affected areas of the face, scalp, ears, and hands where sun damage has occurred.
The active ingredient fluorouracil (5-FU) works by interfering with DNA and RNA synthesis in rapidly dividing cells, causing abnormal skin cells to die off. This leads to inflammation, crusting, and eventual clearing of the treated lesions.
Efudex is a prescription-only medication that should be applied exactly as directed by a healthcare provider. Common side effects include skin irritation, redness, burning, and discoloration at the application site. Patients should avoid sun exposure during treatment and use sunscreen. The medication is for external use only and should not be used during pregnancy.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy