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Drug Class: Commonly Known As: Category:
Zyloprim, Zyloric

Allopurinol - Side Effects, Precautions, and Contraindications

What side effects can Allopurinol cause?

Common side effects include:

  • Diarrhea
  • Upset stomach
    • Take this medication with or after food to reduce stomach upset

When allopurinol is started for gout prevention, the chances of having gout attacks may be higher initially. Do not stop taking this medication without checking with your doctor. Your doctor may prescribe another medication to be taken together to reduce the risk of getting gout attacks during the initial period of this medication.

Very rarely, a bad skin reaction known as Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TENs) may happen. This can cause serious health problems that may sometimes be life threatening. Stop this medication and see a doctor immediately if you have signs like face swelling, blisters or peeling on skin, skin rashes that spread within hours to days.

Very rarely, this medication may also injure or damage the liver. A liver injury may recover on its own. However, in some cases, it may cause serious liver damage. Stop this medication and see a doctor immediately if you notice any dark-coloured urine, light coloured stools, yellowing of skin or eyes.

The symptoms of a drug allergy include one or more of the following:

  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

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

Before taking Allopurinol , what precautions must I follow?

​Inform your healthcare professional if:

  • You are allergic to this medication or any of the other ingredients of this medication.
  • You have history of kidney condition.
  • You are pregnant, planning to become pregnant, or breastfeeding.
  • You are taking any other medications, including supplements, traditional medications and herbal remedies.

It may take a few weeks before you get the full benefits from taking this medication.

Drink enough water (2-3 litres of water a day) unless your doctor has advised you to restrict fluid intake.

Follow the diet plan recommended by your doctor or dietician.

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

​Inform your doctor if you are taking:

  • Warfarin
  • Azathioprine
  • Mercaptopurine
  • Updated on 9/30/2021 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

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