Efudex Topical Cream for the Treatment of Skin Cancer

Topical cream is a standard treatment for basal cell carcinoma, the most common type of skin cancer worldwide. If your healthcare provider has prescribed the topical medication, Efudex (fluorouracil) for your skin cancer treatment, it's crucial to ensure you are using it safely and effectively.

Fluorouracil is available as a generic and also goes by the brand names Tolak, Carac, and Fluoroplex.

This article explains Efudex's uses, side effects, and contraindications.

The Phases of Fluorouracil Effects
Verywell / Cindy Chung

When Is Efudex Indicated?

Efudex is a topical cream used to treat superficial basal cell carcinoma when conventional methods are impractical.

Situations in which Efudex might be appropriate include:

  • Multiple lesions
  • Complex treatment sites on the face or scalp
  • Actinic keratosis (a precancerous skin condition caused by sun exposure)

Treating actinic keratosis, also called solar keratosis, is important because it can lead to more severe and invasive squamous cell carcinoma if left untreated.

Fluorouracil also treats breast, stomach, bowel, and esophageal cancers in its more potent injectable form.

How Efudex Works

Efudex is a chemotherapy drug. Specifically, it is an "antimetabolite" that inhibits a chemical in metabolism.

Efudex interferes with the formation of DNA and RNA molecules, which are essential for cell division and growth. This inhibition results in the death of quickly growing cancerous cells, which absorb more fluorouracil than healthy cells.

Since Efudex stops cells from growing, it can change the skin's appearance where it is applied. These skin changes may be notable during therapy and for several weeks after.

The effect of fluorouracil occurs in four phases:

  • Early Inflammatory Phase
  • Inflammatory Phase
  • Tumor Disintegration Phase
  • Healing Phase

During the first week of application, mild inflammation occurs. During the following weeks, redness and swelling occur with crusting and burning. Next, lesions resolve as the skin exfoliates. Over one to two weeks, new skin grows into the treatment area.


Efudex is a topical form of chemotherapy. The medication stops cell growth and causes the lesions to die. Then, over a couple of weeks, new skin grows in its place.

How Effective Is Efudex?

The success rate of treating basal cell carcinoma with fluorouracil is approximately 90% to 93%. Efudex cream achieves success rates similar to Aldara (imiquimod), another topical cream used for treating skin cancer.

However, a 2016 review suggests that Efudex is best for treating superficial lesions only, unlike imiquimod. That's because while it is successful in treating surface lesions, it can allow tumors to continue to grow beneath the skin.

Notably, the same review reports that recurrence rates drop to 6% when doctors first perform curettage (scraping away the growth).

One of the benefits of Efudex is that, unlike surgery, it is not likely to leave scars or permanently discolor patches of skin. That said, isolated, easily accessible basal cell carcinomas should be treated with surgery since surgical success with such lesions is almost 100%.

Talk to your healthcare provider about which treatment is best for you.


Efudex is an effective treatment for basal cell carcinoma, especially when combined with surgical removal.

How to Use Efudex

For basal cell carcinoma, dermatologists usually recommend applying 5% fluorouracil cream in an amount sufficient to cover the lesions two times per day for three to six weeks. However, sometimes therapy lasts as long as 10 to 12 weeks before the lesions disappear.

Follow these application tips:

  • Use a cotton-tipped applicator or wear gloves.
  • If applied with unprotected fingertips, wash your hands well afterward.
  • Avoid the eyes, nose, and mouth.

Side Effects

Specific side effects that usually do not require medical attention include:

  • Red or dark-colored skin
  • Erosion (loss of the upper layer of skin)
  • Eye irritation, including burning, itching, sensitivity, stinging, or watering
  • Photosensitivity (skin sensitivity to ultraviolet light)
  • Pain and burning of the affected area
  • Dryness, scaling, or swelling of the affected area
  • Skin rash or itching of the affected area
  • Tenderness

Of course, report any side effects to a healthcare professional if they persist or are bothersome. If you experience more serious side effects, be sure to inform your healthcare provider as soon as possible. These include:

  • Abdominal pain
  • Bloody diarrhea
  • Vomiting
  • Fever
  • Chills

Safety Tip

Avoid sunlight as much as possible while using Efudex since it may increase your side effects. If exposed to the sun, wear a hat and use sunscreen.


You should not use Efudex cream should in some situations, including:

  • While pregnant or considering becoming pregnant
  • While breastfeeding
  • If you have a dihydropyridine dehydrogenase (DPD) enzyme deficiency (a hereditary condition that occurs in 3-5% of the population and requires a genetic test to diagnose)
  • If you are undergoing radiation therapy
  • If you have previously had an unusual or allergic reaction to fluorouracil, chemotherapy, other medicines, foods, dyes, or preservatives


Efudex is a topical chemotherapy treatment for basal cell carcinoma. It works by stopping cells from developing and is effective, especially when combined with surgical lesion removal. Common side effects include skin rash and irritation. Less frequently, more severe side effects can occur. Efudex should not be used by those who are pregnant, breastfeeding, with certain health conditions, or allergies to the medication.

Frequently Asked Questions

  • Can I use a moisturizer after applying Efudex?

    If your doctor okays it, you may be able to ease side effects of Efudex by applying a petroleum-based moisturizer such as Aquaphor or Vaseline or an over-the-counter hydrocortisone. These treatments may not be appropriate for everyone, though.

  • Can I apply fluorouracil cream to my face?

    Yes. In fact, fluorouracil treatment is most successful when used on the face and scalp. Typically, it’s rubbed into the skin once or twice a day for several weeks. In some cases, there may be a break in treatment. You will stop taking it and restart a few weeks later.

  • Is Efudex a type of chemotherapy?

    Yes. Efudex is an antimetabolite, a type of chemotherapy drug that stops cells' DNA from copying itself so cancer cells cannot reproduce. They’re used to treat leukemias, cancers of the breast, ovary, and the intestinal tract, as well as other types of cancer.

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7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. National Library of Medicine MedlinePlus. Fluorouracil topical.

  2. U.S. Food and Drug Administration. Efudex Prescribing Information. Valeant Pharmaceuticals.

  3. Lanoue J, Goldenberg G. Basal cell carcinoma: A comprehensive review of existing and emerging nonsurgical therapiesJ Clin Aesthet Dermatol. 2016;9(5):26–36.

  4. American Cancer Society. Local treatments other than surgery for basal and squamous cell skin cancers.

  5. University of Mississippi Medical Center. Efudex.

  6. West DA, Aires DJ. Treatment of actinic keratoses with topical fluorouracil. AFP. 2010;81(10):1186.

  7. American Cancer Society. How Chemotherapy Drugs Work.

By Timothy DiChiara, PhD
Timothy J. DiChiara, PhD, is a former research scientist and published writer specializing in oncology.