Name: Carac


Carac® (fluorouracil cream) Cream, 0.5% , contains fluorouracil for topical dermatologic use. Chemically, fluorouracil is 5-fluoro-2,4(1H, 3H)-pyrimidinedione. The molecular formula is C4H3FN2O2. Fluorouracil has a molecular weight of 130.08.

Carac Cream contains 0.5% fluorouracil, with 0.35% being incorporated into a patented porous microsphere (Microsponge®)↑ composed of methyl methacrylate / glycol dimethacrylate cross polymer and dimethicone. The cream formulation contains the following other inactive ingredients: carbomer 940, dimethicone, glycerin, methyl gluceth-20, methyl methacrylate / glycol dimethacrylate crosspolymer, methylparaben, octyl hydroxy stearate, polyethylene glycol 400, polysorbate 80, propylene glycol, propylparaben, purified water, sorbitan monooleate, stearic acid, and trolamine.

Carac and Lactation

Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known if fluorouracil is excreted in human breast milk or if it will harm your nursing baby.

Carac Dosage


  • The starting dose is typically 12 mg/kg are given intravenously (into the vein) once daily for 4 successive days. The daily dose should not exceed 800 mg.
    • If no toxicity is observed, 6 mg/kg are given on the 6th, 8th, 10th and 12th days unless toxicity occurs.
    • No therapy is given on the 5th, 7th, 9th or 11th days.
    • Therapy is to be discontinued at the end of the 12th day, even if no toxicity has become apparent.
  • In instances where toxicity has not been a problem, it is recommended that therapy be continued using either of the following schedules:
    • Repeat dosage of first course every 30 days after the last day of the previous course.
    • When toxic effects from the first course of therapy have subsided, maintenance dosage of 10 to 15 mg/kg/week as a single dose is recommended. Do not exceed 1 gram per week.
  • Dose and duration of use may be adjusted if you are in poorer health or if you experience certain toxic side effects.


  • Cream
    • Refer to your specific cream product and your doctor's prescribed directions for use. There are different cream formulations with different directions.
  • Topical solution
    • Apply topical solution twice daily in an amount sufficient to cover the lesions.
    • The usual duration of therapy is from 2 to 4 weeks if treating for actinic or solar keratoses.
    • The usual duration of therapy is from 3 to 6 weeks if treating for basal cell carcinoma. Therapy may be required for as long as 10 to 12 weeks.

What is the most important information i should know about fluorouracil topical (carac, efudex, efudex occlusion pack, fluoroplex)?

Do not use fluorouracil topical on skin that is irritated, peeling, or infected or on open wounds. Wait until these conditions have fully healed before using fluorouracil topical.

Fluorouracil topical is in the FDA pregnancy category X. This means that it is known to harm an unborn baby. Miscarriage and birth defects have been reported when fluorouracil topical was applied to mucous membrane areas by pregnant women. Do not use fluorouracil topical if you are pregnant or planning a pregnancy. Discuss with your doctor appropriate forms of birth control before starting treatment with fluorouracil topical.

Fluorouracil topical is available in a number of strengths and forms (creams and solutions). It is very important that you use the correct form and strength. Contact your doctor or pharmacist if you have questions regarding which product to use.

Avoid exposure to sunlight or artificial UV rays (e.g., sun lamps) during and immediately following treatment with fluorouracil topical. Use a sunscreen with a minimum sun protection factor (SPF) 15 and wear protective clothing when sun exposure is unavoidable. Individuals with fair skin may require a sunscreen with a higher SPF rating.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What other drugs will affect Carac (fluorouracil topical)?

It is not likely that other drugs you take orally or inject will have an effect on topically applied fluorouracil. But many drugs can interact with each other. Tell each of your health care providers about all medicines you use, including prescription and over-the-counter medicines, vitamins, and herbal products.

What do I need to tell my doctor BEFORE I take Carac?

  • If you have an allergy to fluorouracil or any other part of Carac (fluorouracil (topical)).
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you have dihydropyrimidine dehydrogenase deficiency.
  • If you are pregnant or may be pregnant. Do not take this medicine if you are pregnant.
  • If you are breast-feeding. Do not breast-feed while you take Carac.

This is not a list of all drugs or health problems that interact with this medicine.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Carac with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

If OVERDOSE is suspected

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.



There is a possibility of increased absorption through ulcerated or inflamed skin.

Information for the Patient:

Patients using Carac should receive the following information and instructions:

1. This medication is to be used as directed. 2. This medication should not be used for any disorder other than that for which it was prescribed. 3. It is for topical use only. 4. Avoid contact with the eyes, eyelids, nostrils, and mouth. 5. Cleanse affected area and wait 10 minutes before applying Carac. 6. Wash hands immediately after applying Carac. 7. Avoid prolonged exposure to sunlight or other forms of ultraviolet irradiation during treatment, as the intensity of the reaction may be increased. 8. Most patients using Carac get skin reactions where the medicine is used. These reactions include redness, dryness, burning, pain, erosion (loss of the upper layer of skin), and swelling. Irritation at the application site may persist for two or more weeks after therapy is discontinued. Treated areas may be unsightly during and after therapy. 9. If you develop abdominal pain, bloody diarrhea, vomiting, fever, or chills while on Carac therapy, stop the medication and contact your physician and/or pharmacist. 10. Report any side effects to the physician and/or pharmacist.

Laboratory Tests:

To rule out the presence of a frank neoplasm, a biopsy may be considered for those areas failing to respond to treatment or recurring after treatment.

Carcinogenesis, Mutagenesis, and Impairment of Fertility:

Adequate long-term studies in animals to evaluate carcinogenic potential have not been conducted with fluorouracil. Studies with the active ingredient of Carac, fluorouracil, have shown positive effects in in vitro and in vivo tests for mutagenicity and on impairment of fertility in in vivo animal studies.

Fluorouracil produced morphological transformation of cells in in vitro cell transformation assays. Morphological transformation was also produced in an in vitro assay by a metabolite of fluorouracil, and the transformed cells produced malignant tumors when injected into immunosuppressed syngeneic mice. Fluorouracil has been shown to exert mutagenic activity in yeast cells, Bacillus subtilis, and Drosophila assays. In addition, fluorouracil has produced chromosome damage at concentrations of 1.0 and 2.0 mcg/mL in an in vitro hamster fibroblast assay, was positive in a microwell mouse lymphoma assay, and was positive in in vivo micronucleus assays in rats and mice following intraperitoneal administration. Some patients receiving cumulative doses of 0.24 to 1.0 g of fluorouracil parenterally have shown an increase in numerical and structural chromosome aberrations in peripheral blood lymphocytes.

Fluorouracil has been shown to impair fertility after parenteral administration in rats. Fluorouracil administered at intraperitoneal doses of 125 and 250 mg/kg has been shown to induce chromosomal aberrations and changes in chromosome organization of spermatogonia in rats. In mice, single-dose intravenous and intraperitoneal injections of fluorouracil have been reported to kill differentiated spermatogonia and spermatocytes at a dose of 500 mg/kg and produce abnormalities in spermatids at 50 mg/kg.

Pediatric Use:

Actinic keratosis is not a condition seen within the pediatric population, except in association with rare genetic diseases. Carac should not be used in children. The safety and effectiveness of Carac have not been established in patients less than 18 years old.

Geriatric Use:

No significant differences in safety and efficacy measures were demonstrated in patients age 65 and older compared to all other patients.



Nursing Women:

It is not known whether fluorouracil is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from fluorouracil, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Fluorouracil topical Pregnancy Warnings

Use is contraindicated. AU TGA pregnancy category: D US FDA pregnancy category: X Comments: -This drug can cause fetal harm when administered to a pregnant woman. -Cases of ventricular septal defect, miscarriage, cleft lip, and cleft palate have been reported with topical administration of this drug. -If this drug is used during pregnancy, or if the patient becomes pregnant while using this drug, the patient should be apprised of the potential hazard to the fetus.

Animal reproduction studies have not been conducted with the topical formulation of this drug; however, when given IV at equivalent human doses, this drug was embryotoxic and teratogenic. There are no controlled data in human pregnancy. AU TGA pregnancy category D: Drugs which have caused, are suspected to have caused or may be expected to cause, an increased incidence of human fetal malformations or irreversible damage. These drugs may also have adverse pharmacological effects. Accompanying texts should be consulted for further details. US FDA pregnancy category X: Studies in animals or humans have demonstrated fetal abnormalities and/or there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience, and the risks involved in use of the drug in pregnant women clearly outweigh potential benefits.