Drugs Information Online
Drugs and diseases reference index

Drugs and diseases reference index

Drugs A-Z List

Diseases & Conditions A-Z List

Herbs & Supplements

Medical Dictionary

Full Article

Popular Drugs

Popular Diseases & Conditions

Drugs reference index «Allopurinol»


Pronunciation: (AL-oh-PURE-ee-nahl)Class: Agent for gout, Antimetabolite

Trade Names:Aloprim- Powder for injection, lyophilized 500 mg

Trade Names:Zyloprim- Tablets 100 mg- Tablets 300 mg

Apo-Allopurinol (Canada)


Inhibits xanthine oxidase, the enzyme responsible for conversion of hypoxanthine to xanthine and then to uric acid.



About 90% absorbed from GI tract. T max is 1.5 h (allopurinol) and 4.5 h (oxipurinol). C max is 3 mcg/mL (allopurinol 300 mg) and 6.5 mcg/mL (oxipurinol).


Rapidly oxidized to oxipurinol.


About 20% is excreted in the feces. Allopurinol is essentially cleared by glomerular filtration, whereas oxipurinol is reabsorbed in the kidney tubules. T 1/2 , plasma is about 1 to 2 h (allopurinol) and about 15 h (oxipurinol).


Uric acid decreases in about 2 to 3 days.


May require a week or more of treatment.


Xanthine oxidase inhibition is maintained over 24 h; however, uric acid levels may not return to pretreatment levels until 7 to 10 days following cessation of therapy.

Indications and Usage


Treatment of primary or secondary gout, hyperuricemia resulting from chemotherapy for malignancies, recurrent calcium oxalate renal calculi.

Tablets and injections

Management of patients with leukemia, lymphoma, and solid tumor malignancies when concurrently receiving cancer therapy that causes elevations of serum and urinary uric acid levels. Use injection in patients who cannot tolerate oral therapy.

Unlabeled Uses

Prevention of fluorouracil-induced stomatitis and fluorouracil-induced granulocyte suppression.


Standard considerations.

Dosage and Administration

Control of Gout/HyperuricemiaAdults

PO 100 to 800 mg/day. For amounts over 300 mg, give divided doses.

Secondary Hyperuricemia Associated with MalignanciesChildren 6 to 10 yr of age

PO 300 mg/day.

Children under 6 yr of age

PO 150 mg/day.

Prevention of Uric Acid Nephropathy in Vigorous Chemotherapy of Neoplastic DiseaseAdults

PO 600 to 800 mg/day for 2 to 3 days.

Reduction of Risk of Acute Gouty AttacksAdults (initial dose)

PO 100 mg/day, increased by 100 mg at weekly intervals until adequate response is achieved or max recommended dose (800 mg/day) is reached.

Leukemia, Lymphoma, Solid Tumor MalignanciesAdults

IV 200 to 400 mg/m 2 /day (max 600 mg/day).


IV Starting dose 200 mg/m 2 /day.

Renal Function ImpairmentPO CrCl 10 to 20 mL/min

200 mg/day.

CrCl less than 10 mL/min

No more than 100 mg/day.

CrCl less than 3 mL/min

100 mg/day at extended intervals.

Alternatively, for CrCl greater than 50 mL/min, use 75% of usual daily dose; CrCl 10 to 50 mL/min, use 50% of usual daily dose; CrCl less than 10 mL/min, use 25% of usual daily dose.

IV CrCl 10 to 20 mL/min

200 mg/day.

CrCl 3 to 10 mL/min

100 mg/day.

CrCl less than 3 mL/min

100 mg/day at extended intervals.

Alternatively, for CrCl greater than 50 mL/min, use 75% of usual daily dose; CrCl 10 to 50 mL/min, use 50% of usual daily dose; CrCl less than 10 mL/min, use 25% of usual daily dose.


PO/IV Administer 50% of supplemental dose after dialysis. For continuous renal replacement therapy, dose as for CrCl 10 to 50 mL/min.


Reconstituted solution

Store reconstituted solution at 20° to 25°C; do not refrigerate or dilute product.


Store tablets in tightly closed container in cool location.

Unreconstituted solution

Store unreconstituted powder at room temperature.

Drug Interactions

Aluminum salts, uricosuric agents

May lessen effectiveness of allopurinol.


May increase incidence of ampicillin-induced skin rash.


May enhance bone marrow suppression.


Theophylline Cl may be decreased, leading to toxicity.

Thiopurines (eg, azathioprine, mercaptopurine)

Toxicity of these drugs may be increased.

Drugs that are physically incompatible in solution with allopurinol sodium for injection are the following

amikacin; amphotericin B; carmustine; cefotaxime; chlorpromazine; cimetidine; clindamycin; cytarabine; dacarbazine; daunorubicin; diphenhydramine; doxorubicin; doxycycline; droperidol; floxuridine; gentamicin; haloperidol; hydroxyzine; idarubicin; imipenem plus cilastatin; mechlorethamine; meperidine; metoclopramide; methylprednisolone sodium succinate; minocycline; nalbuphine; netilmicin; ondansetron; prochlorperazine edisylate; promethazine; sodium bicarbonate; streptozocin; tobramycin; vinorelbine tartrate.

Laboratory Test Interactions

None well documented.

Adverse Reactions


Drowsiness; generalized seizure (injectable); headache; neuritis; paresthesias; peripheral neuropathy.


Allergic vasculitis; alopecia; ecchymosis; skin rash. Allergic reactions may be severe and sometimes fatal.


Epistaxis; myopathy; taste disturbance.


Abdominal pain; diarrhea; dyspepsia; gastritis; granulomatous changes; nausea; vomiting.


Renal failure; uremia.


Bone marrow depression; eosinophilia; leukocytosis; leukopenia; thrombocytopenia.


Cholestatic jaundice; elevated liver enzymes; hepatic necrosis; hepatitis; reversible hepatomegaly.


Acute gouty attacks; arthralgia; fever; myopathy; necrotizing angiitis.



Category C .


Excreted in breast milk.


Allopurinol is rarely indicated for use in children, except for hyperuricemia resulting from malignancy or with certain rare inborn errors of purine metabolism.


Discontinue drug at first appearance of skin rash or other signs of allergic reaction. Rash may be followed by more severe hypersensitivity reactions and, rarely, death.

Renal Function

Reduced dose is given in patients with this condition. Drug may exacerbate renal failure in certain patients.

Acute gouty attacks

May occur during initial stages of therapy.

Bone marrow depression

Reported in patients given allopurinol.

Patient Information

  • Encourage patient to focus on weight loss or control.
  • Tell patient to avoid purine-rich foods (eg, organ meats).
  • Caution patient to avoid excessive intake of alcohol.
  • Explain that gouty attacks may not end for 2 to 6 wk after beginning therapy.
  • Instruct patient to stop taking medication and notify health care provider if rash or flu-like symptoms develop.
  • Advise patient that drug may cause drowsiness, and to use caution while driving or performing other tasks requiring mental alertness.

Copyright © 2009 Wolters Kluwer Health.

  • Allopurinol Prescribing Information (FDA)
  • Allopurinol MedFacts Consumer Leaflet (Wolters Kluwer)
  • Allopurinol Detailed Consumer Information (PDR)
  • allopurinol Concise Consumer Information (Cerner Multum)
  • allopurinol Intravenous Advanced Consumer (Micromedex) - Includes Dosage Information
  • Aloprim Prescribing Information (FDA)
  • Zyloprim Prescribing Information (FDA)

See Also...