12-20-2022

UPDATE December 20, 2022: N-acetylcysteine (NAC) back-order

Acetaminophen toxicity is the most common (~10% of all calls) exposure reported to our Poison Centre.

N-acetylcysteine (NAC), the antidote for acetaminophen toxicity, is supplied as a 20% solution (200 mg NAC per mL of diluent). It is usually supplied in 10 mL or 30 mL vials.

The Ontario, Manitoba & Nunavut Poison Centres has recently been made aware of a back-order of the 30 mL vials (Sandoz or Hikma suppliers) and the 10 mL vials (Hikma pharmaceutical). 
There remain 10,000 30mL vials of 20% NAC at CPDN. 

Hikma lot numbers 205211, 205212, 205213, 205214, 205215, 205216, 205262 have been granted extended expiry dates to January 2023 by Health Canada.

A new supply of 30 mL vials (Hikma) is expected to be available for purchase in early January 2023. The 10 mL vials (Hikma) are expected to be available in late January/early February of 2023.

What this means for you?
1.    Do NOT start NAC based on a history of an acetaminophen exposure.
2.    Draw an acetaminophen level and plot the level against time on the Rumack-Matthew nomogram to determine whether NAC is actually indicated. 
3.    Call the Poison Centre for advice in all cases where an acetaminophen level is not available within 8 hours of ingestion.
4.    Consider preparing 500 mL 3% NAC solutions (instead of 1L) as per the Patient Care Resource page.
5.    Never start High Risk NAC unless prompted to by the Poison Centre. In many cases, routine dosing is adequate & will prevent NAC wastage.