Meds and you

Updated 27 September 2013


Allopurinol is indicated to prevent recurring attacks of acute gout, a condition caused by high levels of uric acid.


Allopurinol is the active ingredient of Zyloprim , Puricos, Lonol, Sandoz-allopurinol and Redurate.

General Information

Allopurinol is indicated to prevent recurring attacks of acute gout, a condition caused by high levels of uric acid. Uric acid forms crystal deposits in tissue, often in and around joints, which is the cause of many of the symptoms of gout.

Allopurinol will not stop a gout attack that is already present, and should not be prescribed for the first time during an acute attack as it may cause a further episode. It must be given with colchicine or another anti-inflammatory drug for the first month of treatment, as an acute attack of gout may occur.

Allopurinol is also used to lower high uric acid levels caused by other drugs, such as anticancer drugs.

It is important to keep taking allopurinol regularly, even if it seems to have no immediate effect - It may be 2 to 6 weeks before you see any results with allopurinol

How does it work?

The forming of uric acid in the human body depends on an enzyme called Xantine oxidase. Allopurinol blocks this enzyme, thus reducing uric acid production in the body.

Fast facts

Drug schedule: Schedule 3

Available as: Allopurinol is available as tablets

What does it do? Allopurinol prevents gout

Overdose risk: Medium

Dependence danger: Low

Available as generic: Yes

Only on prescription? Yes

User information

Onset of effect: Within 48 hours.

Duration of action : Up to 24 hours.

Dietary advice: Allopurinol should be taken with 250ml water with or immediately after food. Large doses of vitamin C should be avoided as this increase the possibility of kidney stone formation. A high fluid intake – 2 litres of water a day – is recommended while taking this medication. To prevent gout attacks, beer, wine and purine-rich foods such as liver, kidney, sweetbreads, anchovies and sardines should be avoided.

Stopping this medicine: Do not stop this medication without consulting your prescriber as symptoms may recur.

Prolonged use: No problems are expected with prolonged use of allopurinol. Periodic checks on uric acid levels in the blood and urine, as well as liver and kidney function tests, are recommended and the dose of allopurinol should be adjusted accordingly if necessary.

Special precautions

Consult your doctor before using this drug if you have known liver or kidney disease, or if you are taking any other medication.

Pregnancy: Avoid. Potential risk to the foetus has been reported. Consult your doctor before use, or if you are planning to fall pregnant.

Breastfeeding: Avoid. This medication is passed through breast milk and may affect your baby adversely. Consult your doctor before use.

Porphyria: This medication is safe to use.

Infants and children : Careful monitoring advised when used in children; a reduction in dose is necessary.

Elderly: No special precautions need to be taken.

Driving and hazardous work: Caution is advised as use of this medication may lead to dizziness, light-headedness and/or sedation. Avoid such activities until you know how it affects you.

Alcohol: Concurrent use of abacavir and alcohol-containing products may worsen gout.

Possible side effects

Side effect


Consult your doctor



Only if severe

In all cases










Yellowish tinge to eyes/skin






Sore throat



Chest tightness









Visual disturbances




Drug interactions:

ACE inhibitors (Blood pressure medication)

Increased risk of allopurinol sensitivity, especially in patients with reduced kidney function

Amoxicillin, ampicillin

Increased incidence of allergic skin rashes


Dose of warfarin may have to be adjusted as the elimination of warfarin is prolonged


Risk of azathioprine toxicity is increased - dose has to be adjusted


Dose of carbamazepine may have to be adjusted as the serum levels of carbamazepine is increased


Risk of bone marrow depression


Increased risk of renal toxicity

Iron supplement

Iron concentration in liver may increase


Risk of mercaptopurine toxicity is increased - dose has to be adjusted


Increased risk of theophylline toxicity


Life-threatening hypersensitivity may occur in patients with reduced kidney function

Food interactions:


Alcohol may worsen gout

Disease interactions

Contact your doctor in case of liver/kidney disease or a history of alcohol abuse

Overdose action

An overdose of allopurinol is unlikely to be life threatening; however if a significant excessive dose have been taken, emergency medical attention is suggested.

Recommended dosage

Adults: 100-300mg per day (maximum 900mg per day)

Children under 15 years of age: 10 mg/kg bodyweight daily (Maximum 400 mg per day)

Interesting fact

Allopurinol is sometimes used in the treatment of Leishmaniasis, a disease caused by parasites that is transmitted by the bite of certain species of sand fly.

This material is not intended to substitute medical advice, but is for informational purposes only. Please consult a physician for specific treatment and recommendations.


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