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Allopurinol - Side Effects, Precautions, and Contraindications

What side effects can Allopurinol cause?

The medication is generally well-tolerated. The most common side effects are:

  • Loose stools (diarrhea)
  • Stomach upset
  • Drowsiness (reported by patients occasionally but not common). Avoid driving or operating heavy machinery if it occurs

Before taking Allopurinol, what precautions must I follow?

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

  • Updated on Friday, June 12, 2015
  • Article contributed by Pharmacy, Rheumatology & Immunology Singapore General Hospital

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

    A Health Sciences Authority (HSA) consumer guide is also available for this drug. These consumer guides provide simple, everyday tips on how you can further protect yourselves against unwanted side effects or reactions when using products ranging from western medicines to health supplements to cosmetics.

    For more information, visit the HSA consumer guide on Allopurinol.

    Information provided in the PDF is extracted directly from the source. SingHealth does not alter or vet the content. Please use the information on user's own discretion. Consult your doctor or pharmacist for relevant information.

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