Generic name: allopurinol (AL oh PURE i nol)
Brand name: Aloprim, Zyloprim, Lopurin
Dosage forms: intravenous powder for injection (500 mg); oral tablet (100 mg; 300 mg)
Drug class: Antigout agents, Antihyperuricemic agents
Allopurinol reduces the production of uric acid in the body. Uric acid buildup can lead to gout or kidney stones.
Allopurinol is used to treat gout or kidney stones.
Allopurinol is also used to decrease levels of uric acid in people who are receiving cancer treatment.
Warnings
Allopurinol can lower blood cells that help your body fight infections. This can make it easier for you to bleed from an injury or get sick from being around others who are ill. Your blood may need to be tested often. Visit your doctor regularly.
You should not use this medicine if you have ever had a serious allergic reaction to allopurinol. Stop taking the medicine and call your doctor at once if you have any signs of skin rash (no matter how mild), painful urination, blood in your urine, burning in your eyes, or swelling in your face or throat.
Avoid drinking alcohol. It can make your condition worse. Allopurinol may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
Allopurinol side effects
Stop using this medicine and get emergency medical help if you have signs of an allergic reaction to allopurinol (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;
- little or no urination;
- easy bruising, unusual bleeding;
- numbness, tingling, burning pain;
- worsening gout symptoms; 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 allopurinol side effects may include:
- an increase in gout attacks when you first starting taking allopurinol oral;
- rash;
- drowsiness;
- fever, chills;
- abnormal liver function tests;
- nausea, diarrhea; or
- joint pain.
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.
Before taking this medicine
You should not use allopurinol if you are allergic to it.
To make sure allopurinol is safe for you, tell your doctor if you have ever had:
- kidney disease;
- liver disease;
- diabetes;
- congestive heart failure;
- high blood pressure;
- if you are receiving chemotherapy; or
- if you have a gene variation called HLA-B*58:01 allele (your doctor will test you for this).
Tell your doctor if you are pregnant or breastfeeding.
Do not give this medicine to a child without medical advice.
How should I use allopurinol?
Take allopurinol exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.
Take allopurinol oral with a full glass of water. To reduce your risk of kidney stones forming, drink 8 to 10 full glasses of fluid every day, unless your doctor tells you otherwise.
If this medicine upsets your stomach, take allopurinol oral after a meal.
Allopurinol injection is given as an infusion into a vein if you are unable to take the medicine by mouth. A healthcare provider will give your first dose and may teach you how to properly use the medication by yourself.
You may need to mix the injection with a liquid (diluent) in an IV bag. When using injections by yourself, be sure you understand how to properly mix and store the medicine. Ask your doctor or pharmacist if you don't understand all instructions.
Prepare an injection only when you are ready to give it. Do not use if the medicine has changed colors or has particles in it. Call your pharmacist for new medicine.
You may need frequent medical tests. Even if you have no symptoms, tests can help your doctor determine if allopurinol is effective.
You may have gout attacks more often when you first start taking this medicine oral. Your doctor may recommend other gout medication to take with allopurinol. Keep taking the medicine as directed.
It may take 2 to 6 weeks before you have fewer gout attacks. 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 to eat or avoid.
Store at room temperature away from moisture and heat.
Dosing information
Usual Adult Dose of Allopurinol for Gout:
Dose will vary with the severity of the disease:
Initial dose: 100 mg orally once a day
-Increase in increments of 100 mg weekly until a serum uric level of 6 mg/dL or less is attained
Mild Gout:
-Average maintenance dose: 200 to 300 mg orally once a day
Moderately Severe Tophaceous Gout:
-Average maintenance dose: 400 to 600 mg orally/day in divided doses
Minimal Effective Dose: 100 to 200 mg per day
Maximum Dose: 800 mg per day
Comments:
-Oral doses in excess of 300 mg/day should be given in divided doses, preferably after meals to minimize gastric irritation.
-A gradual dose titration is recommended to reduce the possibility of acute gouty attacks.
-Normal serum urate levels are usually achieved in 1 to 3 weeks.
Use: For the management of patients with signs and symptoms of primary or secondary gout (acute attacks, tophi, joint destruction, uric acid lithiasis, and/or nephropathy).
Usual Adult Dose of Allopurinol for Hyperuricemia Secondary to Chemotherapy:
Parenteral:
200 to 400 mg/m2/day IV as a single infusion or in equally divided infusions at 6, 8, or 12 hour intervals
Maximum dose: 600 mg/day
Oral:
Initial dose: 600 to 800 mg orally in divided doses
Maintenance: Adjust dose as needed based on serum uric acid levels
Maximum dose: 800 mg per day
Comments:
-When possible, therapy should be initiated 24 to 48 hours before the start of chemotherapy; treatment should be discontinued when the potential for overproduction of uric acid is no longer present.
-Oral doses in excess of 300 mg/day should be given in divided doses, preferably after meals to minimize gastric irritation.
-The dose to lower serum uric acid to normal or near-normal varies with the severity of the disease; the above dosing represents suggested doses; serum uric acid levels should serve as an index.
-Fluid intake should be sufficient to maintain a daily urinary output of at least 2 L; neutral or preferably slightly alkaline urine is desirable.
Use: For the management of patients with leukemia, lymphoma, and malignancies who are receiving cancer therapy which causes elevations of serum and urinary uric acid levels; IV therapy is available for patients who cannot tolerate oral therapy.
Usual Adult Dose of Allopurinol for Calcium Oxalate Calculi with Hyperuricosuria:
200 to 300 mg orally once a day or in divided doses
Comments:
-Carefully assess risk versus benefit when initiating therapy and periodically thereafter.
-Dose adjustments should be based on control of hyperuricosuria based on 24-hour urinary urate determinations.
-Clinical experience suggests these patients may benefit dietary changes in addition to drug therapy.
Use: For the management recurrent calcium oxalate calculi in patients whose daily uric acid excretion exceeds 800 mg/day in males or 750 mg/day in females.
Usual Pediatric Dose for Hyperuricemia Secondary to Chemotherapy:
Parenteral:
Initial dose: 200 mg/m2/day IV as a single infusion or in equally divided infusions at 6, 8, or 12 hour intervals
Maximum dose: 600 mg/day
Oral:
Age: Less than 6 years: 150 mg orally once a day or in divided doses
Age: 6 to 10 years: 300 mg orally once a day or in divided doses
Age: Greater than 10 years: 600 to 800 mg orally per day in divided doses
-After 48 hours, evaluate and adjust dose as needed
Comments:
-Oral doses in excess of 300 mg should be administered in divided doses.
-When possible, therapy should be initiated 24 to 48 hours before the start of chemotherapy; treatment should be discontinued when the potential for overproduction of uric acid is no longer present.
-The dose to lower serum uric acid to normal or near-normal varies with the severity of the disease; the above dosing represents suggested doses in children; serum uric acid levels should serve as an index.
-Fluid intake should be sufficient to maintain a daily urinary output of at least 2 L; neutral or preferably slightly alkaline urine is desirable.
Use: For the management of patients with leukemia, lymphoma, and malignancies who are receiving cancer therapy which causes elevations of serum and urinary uric acid levels.
What happens if I miss a dose?
Take the allopurinol oral dose 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 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 allopurinol will affect you. Your reactions could be impaired.
Avoid drinking alcohol. It may worsen your condition.
What other drugs will affect allopurinol?
Tell your doctor about all your other medicines, especially:
- azathioprine or mercaptopurine;
- chlorpropamide;
- cyclosporine;
- 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 interact with allopurinol, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.