5 Fluorouracil

Other Names: Adrucil®

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About This Drug

Fluorouracil is used to treat cancer.It is given in the vein (IV). 

Possible Side Effects

  • Hair loss. Hair loss is often temporary, although with certain medicine, hair loss can sometimes be permanent. Hair loss may happen suddenly or gradually. If you lose hair, you may lose it from your head, face, armpits, pubic area, chest, and/or legs. You may also notice your hair getting thin.
  • Changes in your nail color, nail loss and/or brittle nail
  • Darkening of the skin, or changes to the color of your skin and/or veins used for infusion
  • Rash, itching
  • Nausea and throwing up (vomiting)
  • Loose bowel movements (diarrhea)
  • Ulcers - sores that may cause pain or bleeding in your digestive tract, which includes your mouth, esophagus, stomach, small/large intestines and rectum
  • Soreness of the mouth and throat. You may have red areas, white patches, or sores that hurt.
  • Decreased appetite (decreased hunger)
  • Changes in the tissue of the heart and/or heart attack. Some changes may happen that can cause your heart to have less ability to pump blood.
  • Bone marrow depression. This is a decrease in the number of white blood cells, red blood cells, and platelets. This may raise your risk of infection, make you tired and weak (fatigue), and raise your risk of bleeding.
  • Sensitivity to light (photosensitivity). Photosensitivity means that you may become more sensitive to the sun and/or light. Your eyes may water more, mostly in bright light.
  • Allergic reaction: Allergic reactions, including anaphylaxis are rare but may happen in some patients. Signs of allergic reaction to this drug may be swelling of the face, feeling like your tongue or throat are swelling, trouble breathing, rash, itching, fever, chills, feeling dizzy, and/or feeling that your heart is beating in a fast or not normal way. If this happens, do not take another dose of this drug. You should get urgent medical treatment.
  • Blurred vision or other changes in eyesight

Note: Not all possible side effects are included above.

Warnings and Precautions

  • Hand-and-foot syndrome. The palms of your hands or soles of your feet may tingle, become numb, painful, swollen, or red.
  • Changes in your central nervous system can happen. The central nervous system is made up of your brain and spinal cord. You could feel extreme tiredness, agitation, confusion, hallucinations (see or hear things that are not there), trouble understanding or speaking, loss of control of your bowels or bladder, eyesight changes, numbness or lack of strength to your arms, legs, face, or body, and coma. If you start to have any of these symptoms let your doctor know right away.
  • Side effects of this drug may be unexpectedly severe in some patients. 

Note: Some of the side effects above are very rare. If you have concerns and/or questions, please discuss them with your medical team.

Important Information

  • This drug may be present in the saliva, tears, sweat, urine, stool, vomit, semen, and vaginal secretions. Talk to your doctor and/or your nurse about the necessary precautions to take during this time. 

Treating Side Effects

  • To help with hair loss, wash with a mild shampoo and avoid washing your hair every day.
  • Avoid rubbing your scalp, pat your hair or scalp dry.
  • Avoid coloring your hair.
  • Limit your use of hair spray, electric curlers, blow dryers, and curling irons.
  • If you are interested in getting a wig, talk to your nurse. You can also call the American Cancer Society at 800-ACS-2345 to find out information about the “Look Good, Feel Better” program close to where you live. It is a free program where women getting chemotherapy can learn about wigs, turbans and scarves as well as makeup techniques and skin and nail care.
  • Keeping your nails moisturized may help with brittleness.
  • To help with itching, moisturize your skin several times day.
  • Avoid sun exposure and apply sunscreen routinely when outdoors.
  • If you get a rash do not put anything on it unless your doctor or nurse says you may. Keep the area around the rash clean and dry. Ask your doctor for medicine if your rash bothers you.
  • To help with decreased appetite, eat small, frequent meals.
  • Eat high caloric food such as pudding, ice cream, yogurt and milkshakes.
  • Drink plenty of fluids (a minimum of eight glasses per day is recommended).
  • If you throw up or have loose bowel movements, you should drink more fluids so that you do not become dehydrated (lack water in the body from losing too much fluid).
  • To help with nausea and vomiting, eat small, frequent meals instead of three large meals a day. Choose foods and drinks that are at room temperature. Ask your nurse or doctor about other helpful tips and medicine that is available to help or stop lessen these symptoms.
  • If you get diarrhea, eat low-fiber foods that are high in protein and calories and avoid foods that can irritate your digestive tracts or lead to cramping.
  • Ask your nurse or doctor about medicine that can lessen or stop your diarrhea.
  • Mouth care is very important. Your mouth care should consist of routine, gentle cleaning of your teeth or dentures and rinsing your mouth with a mixture of 1/2 teaspoon of salt in 8 ounces of water or ½ teaspoon of baking soda in 8 ounces of water. This should be done at least after each meal and at bedtime.
  • If you have mouth sores, avoid mouthwash that has alcohol. Also avoid alcohol and smoking because they can bother your mouth and throat.
  • Manage tiredness by pacing your activities for the day.
  • Be sure to include periods of rest between energy-draining activities.
  • To help decrease your risk of infections, wash your hands regularly.
  • Avoid close contact with people who have a cold, the flu, or other infections.
  • Use a soft toothbrush. Check with your nurse before using dental floss.
  • Be very careful when using knives or tools.
  • Use an electric shaver instead of a razor.

Food and Drug Interactions

  • There are no known interactions of fluorouracil with food.
  • Check with your doctor or pharmacist about all other prescription medicines and dietary supplements you are taking before starting this medicine as there are a lot of known drug interactions with fluorouracil. Also, check with your doctor or pharmacist before starting any new prescription or over-the-counter medicines, or dietary supplement to make sure that there are no interactions.

When to Call the Doctor

Call your doctor or nurse if you have any of these symptoms and/or any new or unusual symptoms:

  • Fever of 100.5 F (38 C) or higher
  • Chills
  • Easy bleeding or bruising
  • Trouble breathing
  • Feeling dizzy or lightheaded
  • Feeling that your heart is beating in a fast or not normal way (palpitations)
  • Chest pain or symptoms of a heart attack. Most heart attacks involve pain in the center of the chest that lasts more than a few minutes. The pain may go away and come back or it can be constant. It can feel like pressure, squeezing, fullness, or pain. Sometimes pain is felt in one or both arms, the back, neck, jaw, or stomach. If any of these symptoms last 2 minutes, call 911.
  • Confusion and/or agitation
  • Hallucinations
  • Trouble understanding or speaking
  • Blurry vision or changes in your eyesight
  • Numbness or lack of strength to your arms, legs, face, or body
  • Nausea that stops you from eating or drinking  and/or is not relieved by prescribed medicines
  • Throwing up more than 3 times a day
  • Loose bowel movements (diarrhea) 4 times a day or loose bowel movements with lack of strength or a feeling of being dizzy
  • Lasting loss of appetite or rapid weight loss of five pounds in a week
  • Pain in your mouth or throat that makes it hard to eat or drink
  • Pain along the digestive tract - especially if worse after eating
  • Blood in your vomit (bright red or coffee-ground) and/or stools (bright red, or black/tarry)
  • Coughing up blood
  • Fatigue that interferes with your daily activities
  • Painful, red, or swollen areas on your hands or feet
  • Numbness and/or tingling of your hands and/or feet
  • Signs of allergic reaction: swelling of the face, feeling like your tongue or throat are swelling, trouble breathing, rash, itching, fever, chills, feeling dizzy, and/or feeling that your heart is beating in a fast or not normal way
  • If you think you are pregnant or may have impregnated your partner

Reproduction Warnings

  • Pregnancy warning: This drug may have harmful effects on the unborn baby. Women of child bearing potential should use effective methods of birth control during your cancer treatment. Let your doctor know right away if you think you may be pregnant. 
  • Breastfeeding warning: It is not known if this drug passes into breast milk. For this reason, women should talk to their doctor about the risks and benefits of breast feeding during treatment with this drug because this drug may enter the breast milk and cause harm to a breast feeding baby. 
  • Fertility warning: In men and women both, this drug may affect your ability to have children in the future. Talk with your doctor or nurse if you plan to have children. Ask for information on sperm or egg banking. 

Revised November 2017

This information is intended to provide helpful health information to the general public and is not to be used in place of any medical, health, psychological, or any other kind of personal professional services.  The information herein does not cover all possible uses, actions, precautions, side effects, or interactions of the medicines mentioned, nor is the information intended as medical advice for individual problems or for making an evaluation as to the risks and benefits of taking a particular medication.  The dose, method of administration and contraindications for any administered medication should be confirmed before use.  UPMC specifically disclaims all responsibility for any liability, loss or risk, personal or otherwise, which is incurred as a consequence, directly or indirectly, of the use and application of any medication mentioned herein.