Article: Allopurinol

Allopurinol
Systematic (IUPAC) name
3,5,7,8-tetrazabicyclo[4.3.0] nona-3,5,9-trien-2-one
Identifiers
CAS number	315-30-0
ATC code	M04AA01
PubChem	2094
DrugBank	APRD00435
Chemical data
Formula	C5H4N4O
Mol. weight	136.112 g/mol
Pharmacokinetic data
Bioavailability	?
Protein binding	Negligible
Metabolism	?
Half life	1-2 hours
Excretion	?
Therapeutic considerations
Pregnancy cat.	?
Legal status	Schedule 6 (USA)
Routes	tablet (100-300 mg), or by injection

Allopurinol is a white, powdery drug used to treat gout. Its use in the United States was started in 1964.

It is an isomer of hypoxanthine and inhibits the production of uric acid, the metabolite responsible for gout, by inhibiting the enzyme xanthine oxidase.

Allopurinol can also be given with some cancer treatments (e.g., CHOP) that increase uric acid (tumor lysis syndrome), as well as for kidney stones. These treatments result in large numbers of cells being disposed of by the body, which releases uric acid as part of the breakdown of DNA.

Allopurinol is an analog of the natural purines in the body, and is quickly metabolised to oxipurinol which is also a xanthine oxidase inhibitor.

The side effects of high levels of precursors are usually minor. A small percentage of people develop a rash and must discontinue this drug. The most serious adverse event is a hypersensitivity syndrome consisting of fever, skin rash, eosinophilia, hepatitis, and worsening renal function. In some cases, allopurinol hypersensitivity syndrome.

Allopurinol is marketed by GlaxoSmithKline as Zyloprim, and by Hexal Australia as the generic brand Allohexal. It is also available under the brand name Progout.

This pharmacology-related article is a stub. You can help Wikipedia by expanding it.