Fluorouracil is used to treat cancer of the colon, rectum, breast, stomach, or pancreas.

Fluorouracil is often given in combination chemotherapy with other cancer drugs.

Fluorouracil may also be used for purposes not listed in this medication guide.

Before using fluorouracil tell your doctor about all your medical conditions or allergies, all medicines you use, and if you are pregnant or breastfeeding.

Fluorouracil is given as an infusion into a vein. A healthcare provider will give you this injection.

You may receive your first dose in a hospital or clinic setting to quickly treat any serious side effects.

Fluorouracil is often given in a treatment cycle, and you may need to use the medicine only on certain days of each cycle. Fluorouracil is sometimes given in a continuous infusion over 24 to 46 hours.

How often you need fluorouracil injections will depend on many factors, including side effects and how your body responds to the medicine. Your doctor will determine how long to treat you with this medicine.

Tell your caregivers if you feel any burning, pain, or swelling around the IV needle when fluorouracil is injected.

Fluorouracil can increase your risk of bleeding or infection. You will need frequent medical tests. Your cancer treatments may be delayed based on the results of these tests.

Usual Adult Dose for Colorectal Cancer:

IN COMBINATION WITH LEUCOVORIN, OR IN COMBINATION WITH LEUCOVORIN AND OXALIPLATIN OR IRINOTECAN:
400 mg/m2 by IV bolus on Day 1, followed by 2400 to 3000 mg/m2 as a continuous IV infusion over 46 hours every 2 weeks

WHEN ADMINISTERED IN A BOLUS DOSING REGIMEN IN COMBINATION WITH LEUCOVORIN:
500 mg/m2 by IV bolus on Days 1, 8, 15, 22, 29, and 36 in 8-week cycles

Use: Adenocarcinoma of the colon and rectum

Usual Adult Dose for Breast Cancer:

ADMINISTERED AS A COMPONENT OF A CYCLOPHOSPHAMIDE-BASED MULTIDRUG REGIMEN:
500 or 600 mg/m2 IV on Days 1 and 8 every 28 days for 6 cycles

Use: Adenocarcinoma of the breast

Usual Adult Dose for Stomach Cancer:

ADMINISTERED AS A COMPONENT OF A PLATINUM-CONTAINING MULTIDRUG CHEMOTHERAPY REGIMEN:
200 to 1000 mg/m2 IV as a continuous infusion over 24 hours; the frequency of dosing in each cycle and the length of each cycle will depend on the dose of fluorouracil and the specific regimen administered

Use: Gastric adenocarcinoma

Usual Adult Dose for Pancreatic Cancer:

ADMINISTERED IN COMBINATION WITH LEUCOVORIN OR AS A COMPONENT OF A MULTIDRUG CHEMOTHERAPY REGIMEN THAT INCLUDES LEUCOVORIN:
400 mg/m2 by IV bolus on Day 1, followed by 2400 mg/m2 IV as a continuous infusion over 46 hours every 2 weeks

Use: Pancreatic adenocarcinoma

Tell your doctor if you have ever had:

• a metabolic disorder called DPD (dihydropyrimidine dehydrogenase) deficiency;

• heart problems; or

• bone marrow depression.

Both men and women using fluorouracil should use effective birth control to prevent pregnancy. Fluorouracil can harm an unborn baby if the mother or father is using this medicine.

Keep using birth control for at least 3 months after your last dose. Tell your doctor right away if a pregnancy occurs while either the mother or the father is using fluorouracil.

This medicine may affect fertility (ability to have children) in both men and women. However, it is important to use birth control to prevent pregnancy because fluorouracil can harm an unborn baby.

You should not breastfeed while using this medicine.

Call your doctor for instructions if you miss an appointment for your fluorouracil injection.

Since this medication is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Fluorouracil may cause serious side effects. Call your doctor at once if you have:

• fever (take your temperature each day while receiving fluorouracil);

• severe or ongoing diarrhea;

• vision problems;

• confusion, problems with balance or muscle movement;

• painful mouth sores, red or swollen gums, trouble swallowing, talking, or eating;

• bone marrow suppression--dizziness, pale lips or fingernail beds, fast heart rate, getting easily tired or short of breath;

• "hand and foot syndrome"--pain, blisters, bleeding, or severe rash on the palms of your hands or the soles of your feet;

• heart problems--chest pain or pressure, pain spreading to your jaw or shoulder, irregular heartbeats, nausea, sweating, feeling dizzy or short of breath.

Your cancer treatments may be delayed or permanently discontinued if you have certain side effects.

Common side effects of fluorouracil may include:

• diarrhea;

• mouth sores;

• heart problems; or

• bone marrow suppression.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

If you take a blood thinner (warfarin, Coumadin, Jantoven), you may need to have more frequent "INR" or prothrombin time tests.

Other drugs may affect fluorouracil, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.