N-acetylcysteine (NAC) back-order – Update January 27, 2023

N-acetylcysteine (NAC) back-order – Update January 27, 2023

N-acetylcysteine (NAC) back-order – Update January 27, 2023

Health Canada has further updated Poison Centres as below in regards to the ongoing NAC shortage.

“Hikma confirmed that a new supply of the 30 mL vials was released late last week and have started shipping out. This release includes 16,800 vials and will represent 5-6 weeks of historical demand. Another 42,000 (30 mL) vials are tentatively scheduled for release in early February. Further resupplies totalling 100,000+ (30 mL) vials are expected through mid-February and March, but this is still to be confirmed.

For the 10 mL vials, Hikma is on track to resolve their shortage with a resupply of 50,000 vials in February but we are still waiting for a confirmation on exact time and quantities.“

Hikma, and endorsed by Health Canada, has issued a further extension of expiry dates of the following lot numbers of n-acetylcysteine with the caveat that there may be decreased efficacy & that the impurity l-cysteine can increase over time. Monitoring for such should be in place. The Poison Centre suggests following liver enzymes & function q12h as per usual protocols.

The Poison Centre is also aware that a 600 mg oral tablet of NAC is available in the marketplace. If available to your hospital, and no intravenous preparation of NAC is available, dosing for acetaminophen toxicity is as follows.

Traditional Oral NAC Protocol:    Loading Dose: 140 mg/kg
                                                         Maintenance Dosing: 70 mg/kg every 4 hours
Please contact the Poison Centre for advice regarding oral NAC stopping rules.

In General:

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. Consider using 600 mg oral NAC tablets as above.
6. Never start High Risk NAC unless prompted to by the Poison Centre. In many cases, routine dosing is adequate & will prevent NAC wastage.