Dosage
Allopurinol comes as 100mg to 300mg tablets that you take every day. Follow your doctor's advice on how many tablets to take, and how many times a day.
You'll usually start on a low dose of allopurinol, but if your uric acid level does not come down far enough, your doctor may increase your dose (up to 900mg daily in severe cases).
If you have kidney or liver disease, your doctor may prescribe a lower dose and will monitor you more closely.
You'll have regular blood tests to monitor your uric acid levels.
How to take it
Swallow your allopurinol tablet with water, ideally after food.
You'll usually take it once a day, but if you're on a high dose, your doctor may advise you to split the dose and take it twice a day.
If your doctor has recommended you take allopurinol with lots of fluid, try to drink 2 to 3 litres of fluids every day.
You can take allopurinol at any time of the day. However, try to take your doses at the same time of day each day.
How long to take it for
If allopurinol works for you, you may need to take it for the rest of your life to treat gout and kidney stones.
If you stop allopurinol treatment suddenly, there is a high risk that gout may get worse or you'll get serious side effects.
Only stop taking allopurinol if a doctor tells you to. A doctor will help you to reduce your dose slowly so you do not get serious side effects.
If you forget to take it
If you take allopurinol once a day, take the missed dose as soon as you remember, unless it's almost time to take the next dose. In this case, skip the missed dose and take your next dose at the usual time.
If you take allopurinol twice or more a day and do not remember until your next dose is due, skip the missed dose and take your next dose at the usual time.
Never take 2 doses to make up for a missed dose.
If you often forget to take your medicines, it may help to set an alarm to remind you. You could also ask a pharmacist for advice on ways to help you remember to take your medicines.
If you take too much
Urgent advice: Contact 111 for advice now if:
You take more than your prescribed dose of allopurinol and you have any of these symptoms:
- feeling or being sick (nausea or vomiting)
- diarrhoea
- feeling dizzy or tired
- headaches
- stomach pain
Go to 111.nhs.uk or call 111. If you need advice for a child under the age of 5, call 111.
If you need to go to A&E, do not drive. Ask someone to drive you or call 999 and ask for an ambulance.
Bring the allopurinol packet or leaflet inside it, any remaining medicine, and any other medicines you take.