Allopurinol Allopurinol

Transcription

1 Drug information Allopurinol Allopurinol This leaflet provides information on allopurinol and will answer any questions you have about the treatment. Arthritis Research UK produce and print our booklets entirely from charitable donations.

2 What is allopurinol? Allopurinol is a type of drug known as a xanthine oxidase inhibitor. The body naturally produces a substance called uric acid, which is carried in the blood as a salt called urate. A build-up of urate crystals in and around joints causes the painful inflammation and swelling associated with acute gout. Allopurinol reduces the formation of uric acid by the body and therefore helps keep the urate in the blood at the correct level.

3 At a glance What type of drug is allopurinol? Allopurinol is a xanthine oxidase inhibitor. What does it do? It reduces uric acid levels and keeps urate in the blood at the correct level. What is it used for? It s used to treat gout. How is it taken? The usual starting dose is between 100 mg and 300 mg daily, which may be increased if the dose is ineffective. Are there any side-effects? Side-effects are uncommon, but the most common are skin rashes, drowsiness or dizziness, nausea and vomiting. Allopurinol can also cause an increase in gout symptoms in the first few months.

4 If taken correctly, allopurinol will prevent future acute attacks. Why is allopurinol prescribed? Allopurinol is used for the long-term control and prevention of gout. It s not a treatment for an acute attack of gout. It can lower urate levels, dissolve existing crystals and stop new crystals forming. Allopurinol is the most common of these urate-lowering drugs. You ll be prescribed allopurinol if: you re having recurrent attacks of gout blood tests show that your urate level is high you have damaged joints or kidneys due to gout you have gouty tophi affecting your skin. If taken correctly, allopurinol will prevent future acute attacks and cure gout. When and how do I take allopurinol? Allopurinol is taken in tablet form once daily, preferably after food. The tablet should be swallowed with water. Allopurinol is available in 100 mg and 300 mg strength tablets. Your doctor will advise you about the correct dose. Usually you ll start with between 100 mg and 300 mg daily but you may need to increase the dosage if your blood urate level doesn t come down far enough. Lower doses are used in people with significant kidney or liver disease. You shouldn t start taking allopurinol until an acute attack of gout has completely settled, although sometimes this isn t possible so the treatment may be started while the attack is in a mild phase. Usually, allopurinol is started 2 3 weeks after an acute attack has settled. How long does allopurinol take to work? Allopurinol lowers the level of urate in the blood within a few weeks. However, urate crystals in the tissues dissolve away very slowly and so acute attacks may still occur. Acute attacks will usually stop, often during the first year of treatment with allopurinol. Record your dosage here to help you manage your treatment: How many? What dosage/strength? How often? When?

5 What are the possible side-effects? Most people on allopurinol don t experience side-effects. Some possible side-effects include: skin rashes drowsiness or dizziness nausea vomiting. If you develop a rash you should stop the allopurinol and see your doctor straight away. If you become dizzy or drowsy while taking allopurinol, don t drive or operate machinery, and see your doctor as soon as possible. Even if side-effects occur, it may be possible to restart allopurinol using a special desensitisation course, which involves beginning allopurinol at a very low dose and increasing the dosage gradually. Your doctor may need to discuss this with a hospital specialist or hospital pharmacist. Taking allopurinol can trigger an acute attack of gout in the first few months, so for these first few months you ll usually be given an additional medicine to reduce the risk of a flare of gout. This will be a small dose of either a non-steroidal antiinflammatory drug (NSAID) or colchicine. If you do develop an acute attack of gout while on allopurinol, don t stop taking it. Treat the acute attack as you would normally. Allopurinol is generally needed for life; if you stop, your urate level will slowly build up and your gout may come back. If you develop any new symptoms or there s anything else that concerns you after starting allopurinol, you should tell your doctor or rheumatology nurse specialist as soon as possible. What are the risks? Will it affect vaccinations? You can have vaccinations while on allopurinol. Can I drink alcohol while on allopurinol? Alcohol increases the level of urate in the blood so it s recommended that you should only drink alcohol in small amounts (less than 4 units per week). You should discuss this with your doctor. Does allopurinol affect fertility or pregnancy? It s rare for women to get gout before the menopause, but allopurinol is unlikely to affect fertility. However, we don t know what effect allopurinol has on an unborn baby and so you shouldn t take it if you re pregnant. If you re planning a family or become pregnant while taking allopurinol you should discuss this with your doctor. Does it affect breastfeeding? Some allopurinol will pass into the breast milk but the risk to the baby is unknown. Therefore you shouldn t breastfeed if you re taking allopurinol.

6 What else should I know about allopurinol? Are there any alternatives? A number of other drugs can be used to treat gout. Your doctor and rheumatology nurse specialist will discuss these other options with you. A drug called febuxostat may be used if allopurinol isn t effective or can t be used due to medical reasons. Both these drugs reduce the formation of urate by the body. If neither allopurinol nor febuxostat is suitable, uricosuric drugs (e.g. benzbromarone or suphinpyrazone) may be given as an alternative. Uricosurics reduce urate levels by increasing how much urate passes in the urine. Will I need any special checks while on allopurinol? Your doctor may arrange for you to have a blood test at intervals during the first few months of treatment. This is to check that the urate level in the blood has fallen sufficiently and that the allopurinol dose is therefore correct. Once the urate levels are low and steady, a blood check every few months is enough. Can I take other medicines alongside allopurinol? Some drugs interact with allopurinol, so you should discuss any new medication with your doctor before starting it, and you should always tell any other doctor treating you that you re taking allopurinol. Allopurinol reduces uric acid levels and so keeps urate in the blood at the right level. You should also be aware of the following points: Allopurinol may increase the sideeffects of the immunosuppressant drugs azathioprine and mercaptopurine (your dose of these drugs will be reduced if you need to start allopurinol). Allopurinol may increase the risk of developing a rash with the antibiotics ampicillin or amoxicillin. Allopurinol may increase the effect of warfarin and other drugs that thin the blood (anticoagulants), so you may need to have your blood clotting tested more frequently. Allopurinol isn t a painkiller. You can take NSAIDs or painkillers alongside allopurinol, unless your doctor tells you otherwise. You may be prescribed colchicine or prednisolone alongside allopurinol if you re unable to take NSAIDs.

7 Notes

8 Where can I get more information? Arthritis Research UK is the charity leading the fight against arthritis. We do this by funding high-quality research, providing information and campaigning. We publish over 60 information booklets which help people to understand more about their conditions, its treatment, therapies and how to help themselves. If you would like any further information about allopurinol, or if you have any concerns about your treatment, you should discuss this with your doctor, rheumatology nurse or pharmacist. Get involved! You can help to take the pain away from millions of people in the UK. To get more actively involved, please call us or us at [email protected] or go to: A team of people contributed to this booklet. It was written by Dr Ariane Herrick, who has expertise in the subject. It was assessed at draft stage by consultant and reader in rheumatology Dr Gabrielle Kingsley and rheumatology nurse specialist Sue Shipman. An Arthritis Research UK editor revised the text to make it easy to read, and a nonmedical panel, including interested societies, checked it for understanding. An Arthritis Research UK medical advisor, Prof. Anisur Rahman, is responsible for the content overall. Please note: We have made every effort to ensure that this content is correct at time of publication, but remember that information about drugs may change. This information sheet is for general education only and does not list all the uses and side-effects associated with this drug. For full details please see the drug information leaflet that comes with your medicine. Your doctor will assess your medical circumstances and draw your attention to any information or side-effects that may be relevant in your particular case. This leaflet has been produced, funded and independently verified by Arthritis Research UK. Arthritis Research UK Copeman House, St Mary s Court, St Mary s Gate, Chesterfield, Derbyshire S41 7TD Tel calls charged at standard rate Registered Charity No Arthritis Research UK 2011 Published September /D-ALLO/11-1 This paper is made up of 100% fibre ECF virgin wood fibre, independently certified in accordance with the FSC (Forest Stewardship Council).