Efudix Cream (5-Fluorouracil Cream)

What is Efudix cream and what is it used for?

Efudix cream is used to treat severe sun-damage (Actinic or Solar keratoses), pre-cancerous lesions and simple cancers of the skin.

The active ingredient is Fluorouracil (5% concentration), which is a chemotherapy agent; it is important to follow the directions for use carefully.

Efudix destroys cancerous and pre-cancerous cells, while having little effect on normal cells. The area of abnormal skin becomes very red and inflamed; this may progress to erosions and scabbing, followed by healing. This process shows the Efudix is working. After stopping treatment, your skin will need to heal and the treated area may remain red for a while. The entire process may take one to two months to be completed.

Efudix treats skin conditions related to sun damage, and this is often more generalised than you may have realised. Efudix will attend to these areas of abnormal skin too.

Before you use Efudix cream

Do not use Efudix if:

  • You are allergic or hyper-sensitive to Efudix (Fluorouracil) 
  • You are pregnant or breast-feeding
  • You are using antiviral nucleoside medication e.g. brivudine, sorivudine, used to treat chickenpox or shingles
  • Under 18 years old
  • Have DPD Enzyme Deficiency


  • You may want to delay treatment until after an important social engagement; if you are treating your face, it may look fairly red and unsightly in photos!!!!
  • Efudix is best used in winter as your face will be very sensitive to sunlight during treatment

How to use Efudix cream

  • Efudix is a topical treatment
  • Apply a thin layer to the affected area
  • Use the cream twice a day. If your skin is very fragile, once a day may be all that is required
  • If you are treating a small area, applying a dressing or tape over the area of Efudix at night will improve its efficacy 
  • Wash your hands thoroughly after application or use a cotton bud to apply the cream
  • Avoid getting the cream in your eyes, nose or mouth
  • Never treat an area of skin larger than 23 x 23 cm. This is a absolute maximum and if you are considering treating a large area eg your entire face, it will be more comfortable to treat smaller areas sequentially e.g. one cheek then the other cheek, or both cheeks and then your forehead 
  • The cream needs to be applied for three to four weeks or until the area scabs or bleeds
  • Moisturizer or sunscreen can be applied over the Efudix, 20 minutes after application
  • You must avoid sun exposure during treatment

After Efudix

  • Chlorsig ointment is a topical antibiotic cream that should be applied twice a day until the skin is healed. Alternatives are Vaseline or other simple, plain, unscented moisturizers 
  • Avoid sun exposure for 6 months at least and use a sun screen with SPF > 30 to prevent development of further lesions and aid healing of skin
  • Residual or recurring lesions may require a biopsy or excision

Unwanted side effects

Side effects are generally related to the area where the Efudix is applied. A degree of inflammation is required for the Efudix to work; the greater the inflammation, the better the result.

However, significant itching, burning, severe peeling, intense swelling, blistering, hives or pain is not expected. It is best to stop the cream and discuss with me or your GP. A severe reaction may need a short course of steroid cream to calm and heal the skin.

More generalised side effects are very rare and should you be concerned about them, please stop the Efudix and consult me or your GP.