Efudex (5-Fluorouracil) Treatment

Efudex (5-flurouracil) is a topical chemotherapy cream used to treat pre-cancerous and superficial skin cancers. The cream directly targets and eliminates pre-cancerous and cancerous cells from the skin while having little effect on normal skin cells. The area of atypical and pre-cancerous cells will be affected by the treatment, leading to irritation, redness, inflammation, and may progress to scabbing, erosions, and tenderness. This is followed by a healing stage. These results show that the cream is working. After completing treatment, your skin will heal and may remain red for weeks. The entire healing process may take months.

• Apply a thin film twice daily to the area your provider directed you to treat. 

• Rub the medicine in until it disappears. Then wash your hands thoroughly. 

• Typically, the medication is applied for 2-4 weeks but sometimes as long as 6 weeks for skin cancer treatment. Follow the instructions of your provider. 

• Combination forms (5-Fluorouracil with Calcipotriene) are typically used for shorter durations (sometimes as short as 4 days).  Please follow the instructions provided by your provider.

• 4-7 days after starting treatment, the treated areas will turn pink, then later red. (May be seen earlier with the combination form).

• Scaling, blistering and/or crusting will occur.  Stinging and tenderness can occur.

• Vaseline or Aquaphor can be applied to the scaly or open areas of skin multiple times per day to provide comfort/relief.

• This reaction is expected and necessary for adequate treatment. 

• Contact the office for the following:

  • If you are experiencing significant crusting, pain, or yellowish-green drainage

  • If you experience any flu-like symptoms

• After the treatment is stopped, continue the Vaseline or Aquaphor ointment until crusting/scabbing has resolved.

• You may use over the counter 1% hydrocortisone ointment for up to 7 days to decrease the irritation of the reaction. 

• Complete healing will require up to 1-2 months.  Redness will be slow to fade.

• Your skin will be more sensitive to the sun during and after treatment. Ensure proper use of sunscreen (SPF 30+) prior to sun-exposure to prevent further sun damage and sunburn.

Your provider will want to examine the treated areas after treatment has ended and the skin has had time to heal. Ensure that you have scheduled appropriate follow up.

Efudex is particularly dangerous for dogs and cats, even in very small amounts. Please keep tubes out of reach of pets and do not allow them to lick skin that has been treated.