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

Allopurinol - What is it for

Allopurinol is used to prevent gout, a condition that can cause pain and swelling in the joints.
Gout happens when there is too much uric acid in the blood. Uric acid is a chemical that is produced when the body breaks down certain food.  Allopurinol reduces the production of uric acid, thus lowering the uric acid levels in the body.

Allopurinol is also used in the treatment of uric acid stones and to prevent uric acid levels from going up too high during chemotherapy.

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

Allopurinol - Dosage and How to Use

How should Allopurinol be used?

  • Do not stop taking your medication without checking with your healthcare professional.
  • This medication should be taken with or after food to reduce stomach upset.
  • Take this medication with plenty of water.

What should I do if I miss a dose?

If you forget to take a dose, take it as soon as you remember. Then take your next dose at the usual time. Do not take two doses to make up for the missed dose.

What should I do if I overdose?

Allopurinol - Handling

How should I handle Allopurinol safely?

Allopurinol - Storage

How should I store Allopurinol ?

;#Keep away from children;#Keep in a cool, dry place, away from direct sunlight;#

How should I dispose of Allopurinol safely?

​Pack this medication into a black trash bag and seal it tightly before throwing into the rubbish chute or bin.

Allopurinol - Additional Information

  • 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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