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Drug Class: Commonly Known As: Category:
Antimetabolite Cancer-related

5-Fluorouracil - Side Effects, Precautions, and Contraindications

What side effects can 5-Fluorouracil cause?

Early side effects
  • Mild nausea, vomiting or appetite loss may be experienced.
    There are medicines available, which may prevent or decrease these side effects. If you are given these medicines, take them as directed.
Delayed side effects
  • A drop in the white blood cell counts may occur 7 to 14 days after treatment.
  • Mouth ulcers may occur within several days of treatment.
  • Mild hair loss or thinning may begin several weeks after treatment.
  • Diarrhoea may occur.
  • Skin and nail changes such as dryness, fissuring, darkening (may affect the veins as well) and nail ridging may occur.
  • Hand-foot skin reactions with continuous infusion of fluorouracil may occur after 8 to 9 weeks or earlier. Symptoms may include tingling, redness, swelling, tenderness, skin thickening and peeling.

Inform your doctor if any of the following occurs:

  • Fever of 38°C or higher, chills or sore throat.
  • Diarrhoea lasting longer than 24 hours.
  • Soreness in the mouth for more than 3 days.
  • Unusual bleeding, bruising or black tarry stools.

Before taking 5-Fluorouracil, what precautions must I follow?

What food or medicine must I avoid when I take 5-Fluorouracil?

Updated on Friday, August 17, 2018

This article is contributed by Department of Pharmacy National Cancer Centre Singapore

    The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth


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