Medically reviewed by A Ras MD
What is Tolak?
Tolak Cream is a prescription medicine used to treat skin lesions called actinic keratosis on the face, ears, or scalp.
It is not known if Tolak Cream is safe and effective for use on other areas of the body or to treat problems other than actinic keratosis.
It is not known if Tolak Cream is safe and effective in children.
Tolak (fluorouracil) Cream, 4% contains 40 mg of fluorouracil per gram of white cream for topical application. It is a nucleoside metabolic inhibitor. Chemically, fluorouracil is 5-fluoro-2,4 (1H,3H)-pyrimidinedione. The molecular formula of 5-fluorouracil is C4H3FN2O2, and its molecular weight is 130.1. Its structural formula is:
Tolak Cream contains the following inactive ingredients: arlacel-165, butylated hydroxytoluene, cetyl alcohol, anhydrous citric acid, glycerin, isopropyl myristate, methyl gluceth-10, methylparaben, propylparaben, purified water, peanut oil, sodium hydroxide, stearic acid, and stearyl alcohol. Tolak Cream formulation has an alkaline pH at 8.3 to 9.2.
Mechanism of Action
There is evidence that the metabolism of fluorouracil in the anabolic pathway blocks the methylation reaction of deoxyuridylic acid to thymidylic acid. In this manner, fluorouracil interferes with the synthesis of DNA and to a lesser extent inhibits the formation of RNA. Since DNA and RNA are essential for cell division and growth, the effect of fluorouracil may be to create a thymine deficiency that provokes unbalanced growth and death of the cell. The effects of DNA and RNA deprivation are most marked on those cells that grow more rapidly and take up fluorouracil at a more rapid rate.
What is the most important information I should know about Tolak?
Important: Tolak Cream is for use on skin only (topical). Do not get or apply Tolak Cream on your eyelids or in your eyes, nose, mouth, or in the vagina, because it may cause irritation and swelling in these areas.
Who should not use Tolak?
Do not use Tolak Cream if:
- you are pregnant or may become pregnant. Tolak Cream may harm your unborn child. Stop using Tolak Cream and tell your doctor right away if you become pregnant while using Tolak Cream.
- your body does not make enough of (you are deficient in) the enzyme called dihydropyrimidine dehydrogenase (DPD). If you do not have enough of this enzyme, you may get serious side effects if you use Tolak Cream. Symptoms of serious side effects include: stomach-area abdominal pain, bloody diarrhea, vomiting, fever, and chills.
What should I tell my healthcare provider before using Tolak?
Before using Tolak Cream, tell your doctor about all your medical conditions, including if you:
- are allergic to any of the ingredients in Tolak Cream. Tolak Cream contains peanut oil. See the end of this guide for a list of all of the ingredients in Tolak Cream.
- are pregnant or plan to become pregnant. See “Who should not use Tolak Cream?”
- Females who are able to become pregnant should use an effective method of birth control during treatment with Tolak Cream and for one month after the last dose of Tolak Cream. Talk to your doctor about birth control methods that may be right for you during treatment with Tolak Cream.
- are breastfeeding or plan to breastfeed. It is not known if Tolak Cream passes into your breast milk. You and your doctor should decide if you will use Tolak Cream or breastfeed.
How should I use Tolak?
- Use Tolak Cream exactly as prescribed by your doctor.
- Apply Tolak Cream 1 time each day, to the areas of your skin to be treated, for 4 weeks. Apply Tolak Cream as follows:
- Gently wash, rinse, and pat dry the skin areas to be treated.
- Apply a thin film of the Tolak Cream to the areas to be treated.
- Gently massage Tolak Cream evenly into your skin.
- Avoid contact with other areas of your body, and transfer of Tolak Cream from your body to other people.
- Wash your hands well after you apply Tolak Cream.
What should I avoid while using Tolak?
- Do not cover the treated areas with an airtight dressing.
- Avoid sunlight. Tolak Cream can make your skin sensitive to the sun. You could get severe sunburn. Limit your time in the sun during treatment with Tolak Cream. Talk to your doctor if you get sunburn.
What are the possible side effects of Tolak?
Tolak Cream can cause serious side effects:
- Skin reactions including possible allergic reactions. Most people using Tolak Cream get skin reactions in the treated areas. You may get skin reactions such as:
- dryness or scaling
- stinging or burning
- skin loss (erosion)
- Eye problems. Eye problems have happened with the use of medicines that contain fluorouracil that are applied to the skin. To help prevent getting Tolak Cream in your eyes, or transferring Tolak Cream from another part of your body to your eyes or to another person’s eyes:
- avoid applying Tolak Cream near or around your eyes
- wash your hands well after you apply Tolak Cream
If you accidentally get Tolak Cream in your eyes, or if Tolak Cream is accidentally transferred to another person’s eyes, flush eyes with large amounts of water and get medical help as soon as possible.
- Tolak Cream can cause serious side effects in people who do not have enough of the enzyme dihydropyrimidine dehydrogenase (DPD). See “Who should not use Tolak Cream?” and “What should I tell my healthcare provider before using Tolak Cream?” Stop using Tolak Cream and call your doctor right away if you get any of the following symptoms during treatment with Tolak Cream:
- stomach-area (abdominal) pain
- bloody diarrhea
Tell your doctor if you get any of these skin reactions and they are severe or do not go away.
These are not all the possible side effects of Tolak Cream. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
General information about the safe and effective use of Tolak
Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use Tolak Cream for a condition for which it was not prescribed. Do not give Tolak Cream to other people, even if they have the same symptoms that you have. It may harm them.
You can ask your pharmacist or doctor for information about Tolak Cream that is written for health professionals.
How should I store Tolak?
- Store Tolak Cream between 68°F to 77°F (20°C to 25°C).
- Do not freeze Tolak Cream.
- Do not use Tolak Cream after the expiration date printed on the tube.
Keep Tolak Cream and all medicines out of the reach of children.
PRINCIPAL DISPLAY PANEL – 40 G TUBE CARTON
- NDC 28105-421-40
(fluorouracil) Cream 4%
- Rx only
- For Topical Use Only
Not for Ophthalmic, Oral or Intravaginal Use
- Contains Peanut Oil
- 40 g
- Topical Cream
- Hill Dermaceuticals, Inc.®
What are the ingredients in Tolak?
Active ingredient: fluorouracil
Inactive ingredients: arlacel-165, butylated hydroxytoluene, cetyl alcohol, anhydrous citric acid, glycerin, isopropyl myristate, methyl gluceth-10, methylparaben, propylparaben, purified water, peanut oil, sodium hydroxide, stearic acid, and stearyl alcohol.
SRC: NLM .