Allopurinol is used to reduce the high level of uric acid in your body.
Build-up of uric acid in your body can cause gout, gouty arthritis, kidney or urinary tract stones. This medicine is used to prevent or treat these conditions.
It is also used to treat high levels of uric acid that may occur during cancer treatment.
Allopurinol does not treat sudden gout attacks as it cannot relieve acute pain. Your doctor may give you extra medicines during the early part of Allopurinol therapy to help you cope with acute pain.
Take Allopurinol exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.
Take this medicine after meals. Try to take it at the same time each day.
This medicine must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
If you often forget to take your medicine, let your doctor and pharmacist know.
Individuals who have the gene called HLA-B*58:01 are more likely to develop serious allergic reactions (e.g. rashes with skin peeling or blisters) to Allopurinol. Your doctor may need to perform genetic testing before giving you this medicine to know if it is suitable for you. If you know you have this gene type, alert your doctor.
Inform your doctor if you have the following conditions:
- kidney disease
- liver disease
- thyroid disease
- abnormal iron storage in the body e.g. iron overload
Let your doctor know if you are pregnant or breastfeeding.
Be sure to check with your doctor or pharmacist before giving this medicine to a child. Children may be more sensitive to the side effects.
Why is it important to keep my appointments with the doctor?
Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly.
- Routine blood tests (e.g. uric acid levels, liver and kidney function) may be done while you are being treated with this medicine.
- Regular monitoring for signs of skin reactions or liver damage may also be needed.
Your doctor will advise you about how often you need to have these tests.
Allopurinol may cause drowsiness or dizziness. If affected, do not drive or take part in any activity in which you need to be alert.
Other side effects include any of the following: nausea, vomiting, diarrhoea, abdominal pain, loss of taste, headache, itchiness and hair loss.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- itchy or flaky skin rash, bruising or discolouration of the skin
- rashes with peeling of the skin or blistering of the lips, mouth or eyes accompanied by fever
- fever, swollen lymph glands and joint pain
- yellowing of the skin or eyes, abdominal pain, dark coloured urine, tiredness, swelling in the legs and ankles
- blood in the urine, pain when passing urine or unable to pass urine
Allopurinol may also cause an increase in gout attacks during the start of treatment. Let your doctor know if you experience gout attacks frequently.
This medicine may cause the level of your white blood cells and platelets to drop.
White blood cells help your body to fight infections. A fall in the level of your white blood cells may put you at higher risk for infections, such as coughs, colds and flu, which may lead to more serious infections. Avoid crowded places and people who are sick. Inform your doctor if you have a fever, or a cough or flu that does not go away.
Platelets help your blood to clot when there is a cut in the skin. A fall in the level of your platelets may put you at risk of bleeding more than usual. Do not take part in activities where you may fall or get injured, such as contact sports. Inform your doctor if you get any unusual bruising (large bruises or several bruises, especially if the bruises appeared on their own) or bleeding that takes a long time to stop (for example, too much bleeding when you floss or brush your teeth).
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- mercaptopurine (medicine to treat cancer of the white blood cells)
- medicines used in organ transplant or certain immune disorders e.g. azathioprine, ciclosporin
- dicoumarol (blood-thinning medicine)
- certain antibiotics e.g. amoxicillin, ampicillin
- chlorpropamide (medicine for diabetes)
- phenytoin (medicine for epilepsy)
- medicines for asthma e.g. theophylline
- other medicines for gout e.g. probenecid
- aspirin and other related medicines known as salicylates
- water pills
- vidarabine (medicine for eye infection, herpes and chickenpox)
This list does not include all medicine that may interact with Allopurinol.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
In order to prevent future gout attacks, it is important to be mindful of your diet.
Avoid excessive alcohol intake. Drink plenty of water to keep hydrated.
Avoid foods high in purine, such as organ meat, seafood and oily fish. Other foods with purine content, such as meat, poultry, fish, may be eaten in moderation. Eat a healthy, balanced diet, low in highly processed foods and refined sugar (sugar that is commonly found in processed foods including soft drinks, candies, canned fruits).
Store in a cool, dry place away from the reach of children.
Protect from light and moisture.
Medicines must not be used past the expiry date.