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Drug Class: Commonly Known As: Category:
Antineoplastic Agent Efudix® Adult, Cancer-related

Fluorouracil - Side Effects, Precautions, and Contraindications

What side effects can Fluorouracil cause?

​Certain side effects of this medication are not unusual and may even disappear during treatment. If any of the following effects persist or are severe, consult your doctor.

  • Redness, soreness, scaling and peeling of affected skin
    • This is to be expected. It happens within 1 or 2 weeks of use and may last for several weeks even after you have stopped using the medication. Sometimes a pink, smooth area is left when the treated skin heals. This area will usually fade after 1 to 2 months. Do not stop using this medication without first checking with your doctor.
  • Skin irritation, burning, pain and swelling at the site of application
  • Enlarged lymph nodes may appear transiently
  • This medication may make you more sensitive to the sun
    • Avoid prolonged sun exposure, tanning booths, and sunlamps. Use a sunscreen and wear protective clothing when outdoors.

 If you experience any of the following symptoms, you should stop your medication and see your healthcare professional immediately.

  • Stomach pain
  • Severe or bloody diarrhoea
  • Vomiting
  • Vision changes, eye pain or severe eye irritation
  • Mouth sores
  • Fever, chills, or sore throat; unexplained bruising or bleeding; feeling very tired or weak
  • Symptoms of a drug allergy:
    • Swollen face/eyes/lips/tongue
    • Difficulty in breathing
    • Itchy skin rashes over your whole body

Before taking Fluorouracil , what precautions must I follow?

  • ​Be careful if you are applying the medication around your eyelids, nose and lips and avoid any contact with the eyes or mouth. Wash your hands thoroughly after use.
  • Do not apply the medication on open wounds.
  • If somebody else is helping you to apply the medication, they should take precautions to avoid the medication being absorbed through their skin. It is recommended that they should wear disposable surgical gloves, remove them after use and wash their hands thoroughly.
  • Inform your healthcare professional if:
    • You are allergic to this medication or any of the other ingredients of this medication.
    • You have any red/irritated/open sores on your skin.
    • You are pregnant, planning to become pregnant, or breastfeeding.

What food or medicine must I avoid when I take Fluorouracil ?

​Do check with your healthcare professional if you are taking any other medications or applying any other medications on the skin being treated.

Fluorouracil - Additional Information

  • Updated on 3/31/2021 12:00:00 AM
  • Article contributed by PSS National Medication Information Workgroup PSS National Medication Information Workgroup
The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

​If you take more than the recommended dose, please seek medical advice immediately. The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.

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