5-fluorouracil cream

What are the aims of this leaflet?

This leaflet has been written to help you understand more about 5-fluorouracil (5-FU) cream. It tells you what it is, how it works, how it is used to treat skin conditions, and where you can find out more information about it.

What is 5-FU cream and how does it work?

5-FU cream is a treatment that selectively destroys sun-damaged cells in the skin whilst retaining the normal healthy skin cells.

After a course of 5 FU cream, the skin will become inflamed which  consists of redness, soreness, oozing, crusts and scabs. this reaction will settle over a few weeks. Sometimes your doctor may recommend using a steroid cream to help settle the inflammation more quickly.

In the UK, two forms are available: 5% 5-FU cream (Efudix®) and 0.5% 5-FU combined with 10% Salicylic acid (Actikerall®).

What skin conditions are treated with 5-FU cream?

5-FU cream is prescribed for the treatment of the pre-cancerous skin lesions, actinic keratoses and Bowen’s disease. It is also used for the treatment of superficial basal cell carcinoma.

It is sometimes used to treat other skin conditions such as viral warts, and rarer conditions such as disseminated superficial actinic porokeratosis.

Will 5-FU cream cure my skin condition?

Depending on your skin complaint, 5-FU cream may cure or improve it, but it does not work for everybody. If you have more severe sun-damage, you may require additional courses of treatment.

How do I apply 5-FU cream?

Efudix® cream can be applied with a clean fingertip. Apply a thin layer of the cream to the entire treatment area. If you are using Actikerall® dab the solution on to the treatment site with the brush applicator provided. The solution will dry to leave a film at the site.. Warm water can be used to help loosen the film. Remove the film by peeling just prior to the next application. Specific instructions will be provided by your doctor.

You should wash your hands thoroughly after applying 5-FU cream.

After 20 minutes, you can apply moisturisers and/or make-up as part of your usual skin care routine.

If you have widespread sun-damage it is usually advisable to divide the affected area into smaller areas and to complete treatment in one area before moving on to the next. This will help make the treatment reaction more tolerable. Your doctor will provide further advice about this.

Only cover 5-FU cream with a plaster if advised to do so by your doctor, otherwise leave the treated area uncovered.

How often should I use 5-FU cream?

How often and for how long you should use 5-FU cream will depend on your skin condition and other factors, for example which part of your skin is affected. Efudix® cream is usually applied once or twice a day, for 3-4 weeks when treating actinic keratosis and Bowen’s disease, and for 6 weeks when treating superficial basal cell carcinoma. Occasionally, more prolonged courses may be required. Actikerall® should be applied once daily until the lesions have cleared or for up to a maximum of 12 weeks. Your doctor will recommend a specific treatment schedule for you.

At what time of day should I apply 5-FU cream?

If you are asked by your doctor to use 5-FU cream once a day, you should apply it at night. If twice-daily application is recommended then it is best to apply 5-FU cream in the morning and at night.

When should I not apply 5-FU cream?

5-FU cream should not be used around the eyes or lips, unless specifically recommended by your doctor for use in that area.

Do not apply 5-FU cream if you are pregnant or breastfeeding.

Do not use 5-FU cream if you are allergic to any of its ingredients.

What are the common side effects of 5-FU cream?

As mentioned above, inflammation of the skin is expected, but if the skin becomes very sore or uncomfortable, stop using 5-FU cream. Bathe the area with water, dab the skin dry and apply petroleum jelly daily. The petroleum jelly that you apply should be newly opened and free from potential contamination from fingertips. When the skin settles, you may be able to continue 5-FU cream to complete the treatment course.

If you have any concerns about the severity of the treatment site reaction or are uncertain about whether you should continue treatment, get in touch with your doctor who may recommend a change to your treatment schedule. Your doctor may also have additional treatment site advice, which may include applying a steroid cream to settle the inflammation.

5-FU cream makes your skin more sensitive to sunlight at the site of application, and therefore you should avoid significant sun exposure during and for a while after treatment. This may include modifying activities to limit sun exposure, wearing clothing and/or a hat to cover the treatment site, and the use of sunscreens.

What are the rare side effects of 5-FU cream?

If you have a severe reaction to 5-FU cream, there is a risk of prolonged inflammation and delayed healing and the potential for the development of an ulcer, particularly on the lower legs.

Following a severe reaction, there is a small risk of altered skin pigmentation and scarring.

Skin infections at the site of application of 5-FU cream are rare but possible. If you have concerns about the severity of the skin reaction, get in touch with your doctor.

Very rarely, patients can be allergic to 5-FU cream. This usually causes a severe localised skin reaction. If you have concerns about the severity of your reaction to 5-FU cream, get in touch with your doctor.

Like all medications, 5-FU should be kept out of reach of children and pets.  There have been reports of pets dying or being harmed from licking their owners’ skin after 5-FU had been applied, or from consuming the cream from the tube.

Where can I get more information about 5-FU cream?

Links to other Internet sites:





Please note that the BAD provides web links to additional resources to help people access a range of information about their treatment or skin condition. The views expressed in these external resources may not be shared by the BAD or its members. The BAD has no control of and does not endorse the content of external links.

This leaflet aims to provide accurate information about the subject and is a consensus of the views held by representatives of the British Association of Dermatologists: individual patient circumstances may differ, which might alter both the advice and course of therapy given to you by your doctor.

This leaflet has been assessed for readability by the British Association of Dermatologists’ Patient Information Lay Review Panel

Published on:
October 31, 2023

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