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URL of this page: https://medlineplus.gov/druginfo/meds/a605010.html

Fluorouracil Topical

pronounced as (flure oh yoor' a sil)

Why is this medication prescribed?

Fluorouracil cream and topical solution are used to treat actinic or solar keratoses (scaly or crusted lesions [skin areas] caused by years of too much exposure to sunlight). Fluorouracil cream and topical solution are also used to treat a type of skin cancer called superficial basal cell carcinoma if usual types of treatment cannot be used. Fluorouracil is in a class of medications called antimetabolites. It works by killing fast-growing cells such as the abnormal cells in actinic keratoses and basal cell carcinoma.

How should this medicine be used?

Fluorouracil comes as a solution and a cream to apply to the skin. It is usually applied to the affected areas twice a day. To help you remember to use fluorouracil , apply it around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use fluorouracil exactly as directed. Do not apply more or less of it or apply it more often than prescribed by your doctor.

If you are using fluorouracil to treat actinic or solar keratoses, you should continue using it until the lesions start to peel off. This usually takes about 2 to 4 weeks. However, the lesions may not be completely healed until 1 or 2 months after you stop using fluorouracil.

If you are using fluorouracil to treat basal cell carcinoma, you should continue using it until the lesions are gone. This usually takes at least 3 to 6 weeks, but may take as long as 10 to 12 weeks.

During the first few weeks of treatment, the skin lesions and surrounding areas will feel irritated and look red, swollen, and scaly. This is a sign that fluorouracil is working. Do not stop using fluorouracil unless your doctor has told you to do so.

Apply fluorouracil cream with a nonmetal applicator, a glove, or your finger. If you apply fluorouracil cream with your finger, be sure to wash your hands well immediately afterwards. Do not cover the treated areas with a bandage or dressing unless your doctor tells you to.

Do not apply fluorouracil cream or topical solution to the eyelids or the eyes, nose, or mouth.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before using fluorouracil,

  • tell your doctor and pharmacist if you are allergic to fluorouracil or any other medications.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking, especially other topical medications. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had dihydropyrimidine dehydrogenase (DPD) enzyme deficiency (a lack of a naturally occurring enzyme in your body).
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using fluorouracil , call your doctor immediately. Fluorouracil can harm the fetus.
  • plan to avoid unnecessary or prolonged exposure to sunlight and UV light (such as tanning booths) and to wear protective clothing, sunglasses, and sunscreen. Fluorouracil may make your skin sensitive to sunlight.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Apply the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not apply a double dose to make up for a missed one.

What side effects can this medication cause?

Fluorouracil may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • burning, crusting, redness, discoloration, irritation, pain, itching, rash, or soreness at the site of application

Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, call your doctor immediately:

  • severe stomach pain
  • bloody diarrhea
  • vomiting
  • fever
  • chills
  • severe red skin rash

Fluorouracil may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Carac® Cream
  • Efudex® Cream
  • Efudex® Solution
  • Fluoroplex® Cream

Other names

  • 5-Fluorouracil
  • 5-FU
Last Revised - 05/15/2016