Allopurinol

Not to be confused with haloperidol.

Allopurinol
Clinical data
Trade namesZyloprim, Caplenal, Zyloric, others
AHFS/Drugs.comMonograph
MedlinePlusa682673
License data
Pregnancy
category
Routes of
administration		Oral, intravenous
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability78±20%
Protein bindingNegligible
MetabolismLiver (80% oxipurinol, 10% allopurinol ribosides)
Elimination half-life2 h (oxipurinol 18–30 h)
Identifiers
  • 1H-Pyrazolo[3,4-d]pyrimidin-4(2H)-one
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.005.684 Edit this at Wikidata
Chemical and physical data
FormulaC5H4N4O
Molar mass136.114 g·mol−1
3D model (JSmol)
  • C1=NNC2=C1C(=O)NC=N2
  • InChI=1S/C5H4N4O/c10-5-3-1-8-9-4(3)6-2-7-5/h1-2H,(H2,6,7,8,9,10) checkY
  • Key:OFCNXPDARWKPPY-UHFFFAOYSA-N checkY
  (verify)

Allopurinol is a medication used to decrease high blood uric acid levels.[5] 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.[6][7] It is taken orally (by mouth) or intravenously (injected into a vein).[7]

Common side effects when used orally include itchiness and rash.[7] Common side effects when used by injection include vomiting and kidney problems.[7] While not recommended historically, starting allopurinol during an attack of gout appears to be safe.[8][9] In those already on the medication, it should be continued even during an acute gout attack.[8][6] While use during pregnancy does not appear to result in harm, this use has not been well studied.[1] Allopurinol is in the xanthine oxidase inhibitor family of medications.[7]

Allopurinol was approved for medical use in the United States in 1966.[7] It is on the World Health Organization's List of Essential Medicines.[10] Allopurinol is available as a generic medication.[7] In 2022, it was the 39th most commonly prescribed medication in the United States, with more than 15 million prescriptions.[11][12]

  1. ^ a b "Allopurinol Use During Pregnancy". Drugs.com. Archived from the original on 20 August 2016. Retrieved 20 December 2016.
  2. ^ "Prescription medicines: registration of new generic medicines and biosimilar medicines, 2017". Therapeutic Goods Administration (TGA). 21 June 2022. Archived from the original on 6 July 2023. Retrieved 30 March 2024.
  3. ^ "Allopurinol tablet". DailyMed. 13 December 2023. Archived from the original on 29 February 2024. Retrieved 16 January 2024.
  4. ^ Cite error: The named reference Labelinject was invoked but never defined (see the help page).
  5. ^ Pacher P, Nivorozhkin A, Szabó C (March 2006). "Therapeutic effects of xanthine oxidase inhibitors: renaissance half a century after the discovery of allopurinol". Pharmacological Reviews. 58 (1): 87–114. doi:10.1124/pr.58.1.6. PMC 2233605. PMID 16507884.
  6. ^ a b World Health Organization (2009). Stuart MC, Kouimtzi M, Hill SR (eds.). WHO Model Formulary 2008. World Health Organization. p. 39. hdl:10665/44053. ISBN 9789241547659.
  7. ^ a b c d e f g "Allopurinol". The American Society of Health-System Pharmacists. Archived from the original on 29 April 2016. Retrieved 8 December 2016.
  8. ^ a b Robinson PC, Stamp LK (May 2016). "The management of gout: Much has changed". Australian Family Physician. 45 (5): 299–302. PMID 27166465.
  9. ^ Satpanich P, Pongsittisak W, Manavathongchai S (January 2022). "Early versus Late Allopurinol Initiation in Acute Gout Flare (ELAG): a randomized controlled trial". Clinical Rheumatology. 41 (1): 213–221. doi:10.1007/s10067-021-05872-8. PMID 34406530. S2CID 237156638.
  10. ^ World Health Organization (2023). The selection and use of essential medicines 2023: web annex A: World Health Organization model list of essential medicines: 23rd list (2023). Geneva: World Health Organization. hdl:10665/371090. WHO/MHP/HPS/EML/2023.02.
  11. ^ "The Top 300 of 2022". ClinCalc. Archived from the original on 30 August 2024. Retrieved 30 August 2024.
  12. ^ "Allopurinol Drug Usage Statistics, United States, 2013 - 2022". ClinCalc. Retrieved 30 August 2024.