In this section
General Management of Acute Poisoning Guideline
Paracetamol is the most widely used over-the-counter analgesic agent in the world. It is involved in a large proportion of accidental paediatric exposures and deliberate self-poisoning cases and is the leading pharmaceutical agent responsible for calls to poisons information centres in Australia and New Zealand. Paracetamol is also the single most commonly taken drug in overdoses that lead to hospital presentation and admission. Hepatic failure and death are uncommon outcomes, although paracetamol remains the most important single cause of acute fulminant hepatic failure in Western countries
Consider the possibility of co ingestions, either accidental or deliberate
NAC should be commenced in any patient who reports ingestion of 200 mg/kg or 10g of sustained release paracetamol.
An initial paracetamol concentration should be measured 4 hours post
ingestion or immediately if presentation is >4 hours after
ingestion. If this concentration is above the treatment line then the
full 21 hour infusion of NAC is required.
If the initial paracetamol concentration is below the line then NAC
should be continued and another paracetamol concentration obtained 4
hours after the initial concentration. NAC can be discontinued if both
paracetamol concentrations are below the treatment line.
The standard administration of NAC is a 3 stage infusion giving a total dose of 300 mg/kg:
For patients >110 kg, calculate the dose based on 110 kg body weight.
NAC may be diluted in 5% dextrose or 0.9% saline (normal saline). It can also be diluted in combination dextrose-saline solutions not exceeding these concentrations including 0.45% saline in 5% dextrose, and 0.9% saline in 5% dextrose.
The volume and choice of fluid for each stage of the infusion needs to be appropriate for the age and weight of the child and clinical circumstances. In the adolescent patient, it is generally appropriate to follow the standard published recommendations for NAC administration and use convenient volumes for administration:
However, this results in a total of 1700mls of 5% dextrose which is inappropriate for smaller children.
For smaller children a suggested approach is:
For infants, even smaller volumes may be required. Doses can be diluted in 100 ml bags if available or added to an appropriate volume in a burette.
In all cases, additional maintenance fluids can be given if required, or NAC may be administered in larger volume bags if more convenient.
Note: Monash Health uses
a different NAC infusion protocol to the one contained in this guideline.
Information is available via PROMPT, or by discussing with the Monash on call
Anaphylactoid reactions to NAC may occur (wheeze, rash). In these
cases, cease the infusion for 30 minutes, give promethazine then recommence the
infusion at half the previous rate. Slowly increase the rate until the
desired rate is again reached.
requiring NAC infusion.
Patients requiring care beyond the comfort level of the hospital
Link to NETS/PETS phone number