What is the most important information I should know about allopurinol?
In rare cases, allopurinol may cause a severe allergic reaction. Stop taking this medicine and call your doctor right away if you have painful urination, blood in your urine, burning in your eyes, swelling in your face or throat, skin redness or a rash that spreads and causes blistering and peeling.
You should not use this medicine if you have ever had an allergic reaction to allopurinol.
What is allopurinol?
Allopurinol is used to treat gout and recurrent kidney stones.
Allopurinol is also used to decrease uric acid levels in people that are receiving treatment for certain types of cancer.
Allopurinol may also be used for purposes not listed in this medication guide.
What should I discuss with my healthcare provider before using allopurinol?
You should not use allopurinol if you are allergic to it.
Tell your doctor if you have ever had:
- diabetes;
- congestive heart failure;
- high blood pressure;
- if you are receiving chemotherapy;
- if you have a gene variation called HLA-B*58:01 allele (your doctor can test you for this);
- liver disease; or
- kidney disease.
Allopurinol may harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.
Do not breastfeed while using this medicine, and for at least 1 week after your last dose.
How should I use allopurinol?
Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.
Allopurinol oral is taken by mouth.
Take allopurinol oral with a full glass of water. To reduce your risk of kidney stones, drink 8 to 10 full glasses of fluid every day, unless your doctor tells you otherwise.
Take with food if allopurinol oral upsets your stomach.
Allopurinol injection is injected into a vein by a healthcare provider.
Allopurinol injection is usually given by injection only if you are unable to take medicine by mouth.
You may need frequent medical tests while using this medicine, even if you have no symptoms.
Your kidney and liver function may also need to be tested. Your doctor may change your dose if your kidney function changes.
You may have gout attacks when you first start taking allopurinol oral. Your doctor may recommend another gout medication to take with allopurinol. Keep taking the medicine as directed.
Your symptoms may not improve for up to 2 to 6 weeks. Call your doctor if your symptoms do not improve after 6 weeks.
You may need to follow a special diet to help prevent kidney stones. Follow all instructions of your doctor or dietitian. Learn about the foods you should eat or avoid.
Store at room temperature away from moisture and heat.
What happens if I miss a dose?
Take allopurinol oral as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.
Call your doctor for instructions if you miss an appointment for your allopurinol injection.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid while using allopurinol?
Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired.
What are the possible side effects of allopurinol?
Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
Seek medical treatment if you have a serious drug reaction that can affect many parts of your body. Symptoms may include skin rash, fever, swollen glands, muscle aches, severe weakness, unusual bruising, or yellowing of your skin or eyes.
Stop using allopurinol and call your doctor at once if you have:
- any skin rash, no matter how mild;
- painful urination, blood in the urine;
- inflammation of your blood vessels --numbness or tingling, skin rash, fever, headache, body aches, night sweats, weight loss, feeling or weak or tired;
- signs of infection --fever, chills, sore throat, body aches, unusual tiredness, loss of appetite, bruising or bleeding; or
- liver problems --loss of appetite, weight loss, stomach pain (upper right side), itching, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).
Common side effects may include:
- an increase in gout attacks when you first start taking allopurinol oral;
- rash;
- drowsiness;
- abnormal liver function tests;
- nausea, vomiting, diarrhea; or
- kidney problems --swelling, urinating less, feeling tired or short of breath.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect allopurinol?
Tell your doctor about all your other medicines, especially:
- azathioprine or mercaptopurine;
- chlorpropamide;
- cyclosporine;
- cancer medicine;
- other gout medications;
- an antibiotic such as ampicillin or amoxicillin;
- a blood thinner such as warfarin, Coumadin, Jantoven; or
- a diuretic or "water pill".
This list is not complete. Other drugs may affect allopurinol, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
Where can I get more information?
Your doctor or pharmacist can provide more information about allopurinol.
