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allopurinol

Generic Name: allopurinol (al oh PURE i nole)
Brand names: Zyloprim, Lopurin, Aloprim

What is allopurinol?

Allopurinol reduces the production of uric acid in your body. Uric acid buildup can lead to gout or kidney stones.

Allopurinol is used to treat gout or kidney stones, and to decrease levels of uric acid in people who are receiving cancer treatment.

Allopurinol may also be used for other purposes not listed in this medication guide.

What is the most important information I should know about allopurinol?

Do not use this medication 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. Take each dose 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.

Allopurinol can lower the 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. To be sure your blood cells do not get too low, your blood will need to be tested on a regular basis. Do not miss any scheduled appointments.

Avoid drinking alcohol. It can make your condition worse. Allopurinol can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

What should I discuss with my healthcare provider before taking allopurinol?

Do not use this medication if you have ever had a serious allergic reaction to allopurinol. Before taking allopurinol, tell your doctor if you are allergic to any drugs, or if you have:

kidney disease;
liver disease;
diabetes;
congestive heart failure;
high blood pressure; or
if you are receiving any chemotherapy.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take allopurinol.

FDA pregnancy category C. This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment. Allopurinol can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take allopurinol?

Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.

Your doctor may occasionally change your dose to make sure you get the best results from this medication.

Take each dose 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.

Store allopurinol at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

An overdose of allopurinol is not expected to produce life-threatening symptoms.

What should I avoid while taking allopurinol?

Avoid being near people who have colds, the flu, or other contagious illnesses. Contact your doctor at once if you develop signs of infection.

Allopurinol can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert. Avoid drinking alcohol. It may worsen your condition.

Your doctor may recommend a special diet to help treat your condition. Follow your diet and medication routines very closely.

Allopurinol side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using allopurinol and call your doctor at once if you have any of these serious side effects:

the first sign of any skin rash, no matter how mild;
pain or bleeding when you urinate;
urinating less than usual or not at all;
fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;
bruising, severe tingling, numbness, pain, muscle weakness;
easy bruising or bleeding, unusual weakness;
fever, chills, body aches, flu symptoms;
jaundice (yellowing of the skin or eyes); or
seizure (convulsions).

Less serious side effects may include:

nausea, vomiting, diarrhea;
dizziness or drowsiness;
increased sweating; or
joint pain.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

Allopurinol Dosing Information

Usual Adult Dose for Gout:

Initial: 100 mg orally once a day.
Maintenance: 200 to 300 mg (mild gout) orally once a day or 400 to 600 mg/day (moderately severe tophaceous gout) in divided doses.

Usual Adult Dose for Hyperuricemia Secondary to Chemotherapy:

Initial:
Parenteral: 200 to 400 mg/m2/day to a maximum of 600 mg/day
Oral: 600 to 800 mg/day for 1 to 3 days with consumption of at least 2 L of fluid/day.

Maintenance:
200 to 300 mg/day orally until patient no longer at high risk for developing hyperuricemia.

Usual Adult Dose for Calcium Oxalate Calculi with Hyperuricosuria:

Initial: 200 to 300 mg orally once a day.
Maintenance: 300 mg/day or less.

Usual Adult Dose for Congestive Heart Failure:

Study (n=11) to prevent the formation of superoxide free radicals and improve endothelial function (in NYHA class II to III chronic heart failure): 300 mg orally daily for 1 month

Usual Adult Dose for Cardiothoracic Surgery:

Studies: Coronary Artery Bypass Graft Surgery
600 mg orally one day prior to surgery and another 600 mg orally the day of surgery.

Usual Adult Dose for Leishmaniasis:

Study (n=31 - Cutaneous leishmaniasis: 20 mg/kg/day plus low-dose meglumine antimoniate (30 mg/kg/day) for 20 days.

Case Reports - Visceral leishmaniasis, post renal transplant: 300 mg daily plus meglumine antimoniate (50 mg/kg/day)

Usual Adult Dose for Mania:

Case Reports -- Mania (bipolar I) associated with hyperuricemia: 300 mg orally daily.

Usual Adult Dose for High Risk Percutaneous Transluminal Angioplasty:

Study (n=38) - Primary Percutaneous Transluminal Coronary Angioplasty (PTCA):
400 mg orally administered immediately after admission to the emergency department (approximately 60 minutes before reperfusion) and after primary PTCA was completed.

Usual Adult Dose for Reactive Perforating Collangenosis:

Case Report: 100 mg orally daily.

Usual Pediatric Dose for Hyperuricemia Secondary to Chemotherapy:

Parenteral :
Less than or equal to 10 years: 200 mg/m2/day in 1 to 3 equally divided doses not to exceed 600 mg/24 hours. All doses greater than 300 mg should be given in equally divided doses.
Greater than 10 years: 200 to 400 mg/m2/day administered in 1 to 3 equally divided doses, not to exceed 600 mg/24 hours.

Oral:
Less than 6 years: 150 mg/day orally in 3 divided doses.
6 to 10 years: 300 mg/day orally in 2 to 3 divided doses.
Greater than 10 years: 600 to 800 mg/day in 2 to 3 equally divided doses

Usual Pediatric Dose for Leishmaniasis:

Greater than 5 years old
Study (n=31) - Cutaneous leishmaniasis: 20 mg/kg/day plus low-dose meglumine antimoniate (30 mg/kg/day) for 20 days.

What other drugs will affect allopurinol?

Before taking allopurinol, tell your doctor if you are using any of the following drugs:

azathioprine (Imuran);
chlorpropamide (Diabinese);
cyclosporine (Gengraf, Sandimmune, Neoral);
mercaptopurine (Purinethol);
an antibiotic such as ampicillin (Principen, Omnipen, others) or amoxicillin (Amoxil, Augmentin, Trimox, Wymox);
a blood thinner such as dicoumarol or warfarin (Coumadin); or
a diuretic (water pill).

This list is not complete and there may be other drugs that can interact with allopurinol. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Where can I get more information?

Your pharmacist can provide more information about allopurinol.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed
Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.