04/07/2015 05:10 EDT | Updated 06/07/2015 05:59 EDT

Expired Alesse birth control exposes 'deficiency'

The risk of pregnancy among women who took expired Alesse birth control pills is probably low, experts say, but the fact the pills were dispensed reflects quality control issues at two levels.

Shoppers Drug Mart urged customers in Alberta to check the expiry date on birth control pills purchased in the last three weeks after the company identified about 100 customers received expired product.

The lot of Alesse 21 in question caries an expiry date of September 2014. It was dispensed to about 100 people between March 16 and April 1, 2015, Shoppers said.

Shoppers spokesman Ashesh Desai apologized to those affected.

As soon as Shopper's Drug Mart recognized that there was expired product in the stores, all patients who could have been impacted were contacted immediately, Desai said.

Shoppers attributed it to human error at their distribution centre in Calgary, which resulted in an incorrect data entry in their inventory system. Expired product was then shipped to stores in British Columbia, Alberta, Saskatchewan and Manitoba and dispensed to patients.

Desai said customers potentially affected outside of Alberta were all called and informed of the mistake, which was pointed out to them by a customer. The company offered immediate replacements of the expired product and gave information and counselling.

Alesse's manufacturer, Pfizer Canada, said Shoppers advised the company as soon as they become aware the expired product was dispensed.

"If a Pfizer product is expired, we do not recommend using it," Vincent Lamoureux, director of corporate affairs at Pfizer Canada said in an email.

It's best for manufacturers to be conservative in setting expiry dates for their products, said Philip Emberley, director of pharmacy innovation with the Canadian Pharmacists Association in Ottawa.

Back-up birth control 

"They probably are OK. It is disconcerting, however," Emberley said.

"Pharmacy practice dictates that expiry dates be checked prior to medication being dispensed. I know that it can create a certain amount of angst when a patient receives expired product because these questions go through their minds, especially with something as important as birth control as it can prevent an undesired pregnancy. Having said that, based on all the information we have, chances are these medications are still effective."

Patients trust pharmacists not to miss an expiry date, which is part of their standard of practice, said Emberley. He holds a PhD in pharmacy.

Dr. Jennifer Blake is the CEO of the Society of Obstetricians and Gynecologists of Canada in Ottawa.

"I would take the remaining pills back to the pharmacy and I would exchange them and I would probably use a back-up method just to be doubly sure for the remainder of the month. Get yourself on product that is up to date. The odds are everything is going to be fine but you never want to be taking unnecessary risks when it comes to birth control," Blake advised. 

It's unlikely disciplinary action will be taken against the pharmacists in this case, said Ray Joubert, registrar with the Saskatchewan College of Pharmacists.

But Joubert said his college will follow up to see what pharmacists are doing and future inspections could include monitoring how pharmacists check expiry dates because they are obliged to dispense the highest quality product for all of their inventory.

"Some human error contributed to a system deficiency," Joubert said. The error wasn't immediately picked up at the distribution centre or the pharmacies. 

"We would expect those pharmacies to do root-cause analysis to ensure they've identified all of the causes and then based on that, taken the steps necessary to prevent recurrence of a similar event," Joubert said.

Emberley encouraged customers to also check the expiry dates on products as a third line of defence after the company and pharmacist.

Shoppers provided a list of store locations in Alberta that may have dispensed expired birth control.