NAPQI

NAPQI
Clinical data
Other namesN-Acetyl-p-benzoquinone imine; N-Acetylimidoquinone
Identifiers
  • N-(4-Oxo-1-cyclohexa-2,5-dienylidene)acetamide
CAS Number
PubChem CID
IUPHAR/BPS
ChemSpider
UNII
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.168.312 Edit this at Wikidata
Chemical and physical data
FormulaC8H7NO2
Molar mass149.149 g·mol−1
3D model (JSmol)
  • CC(=O)N=c1ccc(=O)cc1
  • InChI=1S/C8H7NO2/c1-6(10)9-7-2-4-8(11)5-3-7/h2-5H,1H3 checkY
  • Key:URNSECGXFRDEDC-UHFFFAOYSA-N checkY
 ☒NcheckY (what is this?)  (verify)

NAPQI, also known as NAPBQI or N-acetyl-p-benzoquinone imine, is a toxic byproduct produced during the xenobiotic metabolism of the analgesic paracetamol (acetaminophen).[1] It is normally produced only in small amounts, and then almost immediately detoxified in the liver.

However, under some conditions in which NAPQI is not effectively detoxified (usually in the case of paracetamol overdose), it causes severe damage to the liver. This becomes apparent 3–4 days after ingestion and may result in death from fulminant liver failure several days after the overdose.

  1. ^ Mehta, S. (25 August 2012). "Metabolism of Paracetamol (Acetaminophen), Acetanilide and Phenacetin | Medicinal Chemistry | PharmaXChange.info". pharmaxchange.info. Archived from the original on 11 May 2022. Retrieved 29 August 2012.