Isomer hipoksantin, sanggup menghambat oksidase xantin dan dengan demikian mereduksi serum dan tingkat urin pada asam urat; digunakan untuk pengobatan hiperurikemia dari gout dan juga dapat digunakan untuk pengobatan diskrasia darah atau kemoterapi kanker dan sebagai terapi profilaksis dari pembentukan batu ginjal yang berulang.

Merriam-Webster Online Dictionary
allopurinol (noun)
a drug CHNO used to promote excretion of uric acid - 5 4 4
Allopurinol (Wikipedia)
Allopurinol V.1.svg
Allopurinol 3d structure.png
Clinical data
Trade names Zyloprim, Caplenal, Zyloric, others
AHFS/ Monograph
MedlinePlus a682673
  • C(USA)
Routes of
by mouth (tablet), IV
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability 78±20%
Protein binding Negligible
Metabolism liver (80% oxypurinol, 10% allopurinol ribosides)
Biological half-life 2 h (oxypurinol 18-30 h)
CAS Number
PubChem CID
ECHA InfoCard 100.005.684
Chemical and physical data
Formula C5H4N4O
Molar mass 136.112 g/mol
3D model (Jmol)

Allopurinol, sold under the brand name Zyloprim among others, is a medication used to decrease high blood uric acid levels. It is specifically used to prevent gout, prevent specific types of kidney stones, and for the high uric acid levels that can occur with chemotherapy. It is taken by mouth or injected into a vein.

Common side effects when used by mouth include itchiness, and rash. Common side effects when used by injection include vomiting and kidney problems. Starting allopurinol during an attack of gout is not recommended; however, continuing the medication is okay. While use during pregnancy does not appear to result in harm, this use has not been well studied. Allopurinol is in the xanthine oxidase inhibitor family of medications.

Allopurinol was approved for medical use in the United States in 1966. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. Allopurinol is available as a generic medication. The wholesale cost in the developing world is about 0.81 to 3.42 USD per month. In the United States a month of treatment costs less than 25 USD.