Acetylcysteine in paracetamol poisoning: a perspective of 45 years of use

Abstract

Paracetamol poisoning was first reported in 1966. The development of antidotes followed within 10 years, and by 1980 acetylcysteine (NAC) was acknowledged as the optimal therapy available. This article examines the history of the development of NAC and recent developments in its use. We offer suggestions for improvements in the way NAC may be administered and outline new developments that should have major impacts on the way we manage paracetamol poisoning in the near future.

Fig. 1. Examples of nomograms for decisions on use of acetylcysteine in clinical use, showing paracetamol concentration and time after ingestion. Left panel is the present UK nomogram (‘100 mg’ line) on a linear scale. On the right is shown the nomogram originally determined by Rumack and Matthew (‘150 mg’ line) and the original UK (‘200 mg’ Prescott line) both on log scales. The markers on the graphs show timing and sampling of 2 examplar patients, one () who developed hepatotoxicity at a concentration above UK but below other current nomograms, and one () who had no hepatotoxicity, despite having a concentration well above all current treatment lines.