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Read time: 9 mins
Last updated: 06 May 2020
Published: 24 Jul 2020

4.1 Therapeutic indications

N-acetylcysteine is indicated for the treatment of paracetamol overdose in patients:

a) who have taken a staggered overdose irrespective of plasma paracetamol level. Staggered is defined as an overdose where the paracetamol was ingested over a period of 1 hour or more; or

b) where there is any doubt over the time of the overdose, irrespective of plasma paracetamol level; or

c) who present with a plasma paracetamol level on or above a line joining points of 100mg/L at 4h and 15mg/L at 15h (see below nomogram).

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Drug Licencing

Drugs appearing in this section are approved by UK Medicines & Healthcare Products Regulatory Agency (MHRA), & the European Medicines Agency (EMA).