HealthPRO Canada News

July 28, 2020

Use of CAS Registry Numbers as unique identifiers in compounding processes has the potential to reduce medication errors, save lives


In 2016, eight-year-old Andrew Sheldrick died due to a medication error resulting from a mistake made by an independent compounding pharmacy.

Shortly following this incident, the Institute for Safe Medication Practices (ISMP) Canada published a number of recommendations to prevent this from happening again, including that each ingredient in compounding formulas should have a unique identification number.

One such identifier is a Chemical Abstracts Services (CAS) Registry Number®, a unique, unmistakable and internationally recognized numeric attribute for chemical substances.

When compounding formulas include commercially available products as ingredients, the DIN or NPN included on the compounding worksheet can be used as a secondary verification point. For chemical ingredients, the CAS RN® displayed on most chemical product labels distributed in Canada can be added to the worksheet as the secondary check to help prevent adverse medication events.

“Compounding of medications is a high-risk activity that results in a final product for which ingredients cannot be verified through physical examination,” said Sylvia Hyland, Vice President, Operations and Privacy Officer, ISMP Canada. “Our recommendation to include unique identifiers for bulk chemicals is an important step in helping to safeguard patients.”

Melissa Sheldrick, Patient and Family Advisor with ISMP Canada added “the learning that has come from Andrew’s death will drive the much-needed safety improvements throughout the system.”

To assist hospitals in procuring the correct products, HealthPRO has added the CAS RN® to its online contracting portal, accessed by over 1,300 hospitals across the country.

“By ensuring that this number is visible in our contracting system, we are doing our part to foster safe medication management,” said Christine Donaldson, Vice President, Pharmacy at HealthPRO.”