N-acetylcysteine: 50 years since the discovery of an antidote that has changed the prognosis of acetaminophen poisoning


Por: Nogué-Xarau S, Martínez-Sánchez L, García-Peláez M, Fernández de Gamarra-Martínez E, Pi-Sala N, Gispert-Ametller À, Salgado-García E and Aguilar-Salmerón R

Publicada: 1 may 2026 Ahead of Print: 1 may 2026
Resumen:
Acetaminophen is one of the most widely used drugs in clinical practice due to its analgesic and antipyretic properties. However, overdose is one of the leading causes of severe acute liver failure. N-acetylcysteine, introduced as an antidote in 1974, has revolutionized the management of this intoxication by reducing hepatotoxicity and mortality associated with acetaminophen toxicity. At the end of the 19th century, acetaminophen was identified as the main active metabolite of phenacetin and acetanilide. Its therapeutic use began to gain popularity in the 1950s and later became one of the main drugs involved in suicide attempts, particularly among adolescents and young adults. Acetaminophen-induced hepatotoxicity was first described in 1966, establishing that an overdose could lead to fulminant hepatic necrosis. In 1975, Rumack and Matthew published a nomogram that allowed stratification of hepatic toxicity risk based on plasma drug levels. The mechanism of hepatotoxicity was elucidated in the early 1970s when it was discovered that acetaminophen is metabolized by cytochrome P450 into a highly reactive intermediate, N-acetyl-p-benzoquinoneimine, which is normally neutralized by hepatic glutathione. In overdose situations, glutathione depletion leads to hepatic necrosis. Based on these findings, sulfhydryl-containing agents such as cysteamine and methionine were introduced as antidotes, but N-acetylcysteine ultimately proved to be the most effective treatment. Since its introduction, N-acetylcysteine administration protocols have evolved to optimize efficacy and minimize adverse effects. Protocols such as the Scottish and Newcastle Acetylcysteine Protocol and the Two Bags regimen have simplified dosing and reduced the incidence of anaphylactoid reactions. Over the past 50 years, N-acetylcysteine has saved thousands of lives and remains the gold-standard antidotal treatment for acetaminophen poisoning. (c) 2025 The Authors. Published by Elsevier Espa & ntilde;a, S.L.U. on behalf of Sociedad Espa & ntilde;ola de Farmacia Hospitalaria (S. E.F.H). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Filiaciones:
Nogué-Xarau S:
 Grupo de Antídotos, Societat Catalana de Farmàcia Clínica, Barcelona, España

 Fundación Española de Toxicología Clínica, Barcelona, España

Martínez-Sánchez L:
 Grupo de Antídotos, Societat Catalana de Farmàcia Clínica, Barcelona, España

 Servicio de Urgencias, Institut de Recerca Sant Joan de Déu, Esplugues de Llobregat, Barcelona, España

García-Peláez M:
 Grupo de Antídotos, Societat Catalana de Farmàcia Clínica, Barcelona, España

 Servicio de Farmacia, Hospital General de Granollers, Barcelona, España

Fernández de Gamarra-Martínez E:
 Grupo de Antídotos, Societat Catalana de Farmàcia Clínica, Barcelona, España

 Servicio de Farmacia, Hospital de la Santa Creu i Sant Pau, Barcelona, España

Pi-Sala N:
 Grupo de Antídotos, Societat Catalana de Farmàcia Clínica, Barcelona, España

 Servicio de Farmacia, Hospital de Figueres, Figueres, España

Gispert-Ametller À:
 Grupo de Antídotos, Societat Catalana de Farmàcia Clínica, Barcelona, España

 Servicio de Urgencias, Hospital Universitario Doctor Josep Trueta, Girona, España

Salgado-García E:
 Grupo de Antídotos, Societat Catalana de Farmàcia Clínica, Barcelona, España

 Área de Urgencias, Hospital Clínic, Barcelona, España

Aguilar-Salmerón R:
 Grupo de Antídotos, Societat Catalana de Farmàcia Clínica, Barcelona, España

 Servicio de Farmacia, Hospital Universitario Doctor Josep Trueta, Girona, España
ISSN: 11306343





FARMACIA HOSPITALARIA
Editorial
ELSEVIER SCIENCE INC, STE 800, 230 PARK AVE, NEW YORK, NY 10169, España
Tipo de documento: Article
Volumen: 50 Número: 3
Páginas: 162-166
WOS Id: 001765491500001
ID de PubMed: 40835518
imagen gold

MÉTRICAS