Cda Drug Shortages 20120308

It’s unclear what is behind the rise in incidents of substandard medicines in Canada. (Jacques Boissinot/Canadian Press)

The number of recalls of defective prescription medicines in Canada has increased over the last nine years, British researchers have found.

The number of defective medicines reported by Health Canada increased from 42 in 2005 to 143 in 2013,Tariq Almuzaini and his colleagues reported in the medical journal BMJ Open.

The two most common types of defects were:

  • Stability, such as active ingredients that degraded, or oversized tablets, such as morphine tablet recalls in Canada that raised the risk of patients taking as much as double the strength stated on the bottle. A total of 205 incidents of stability defects were identified during the study period.
  • Contamination by foreign substances or microbes, such as bacteria in solutions for injection. There were 139 incidents of contamination issues.

"Most of the failures were related to stability issues, raising the need to investigate the root causes and for stringent preventative measures to be implemented by manufacturers," the study’s authors wrote.

It’s unclear whether the rise in incidents of substandard medicine were related to improved detection by Health Canada or if manufacturers are producing more substandard medicines, the researchers said.

Since Health Canada’s adverse reaction database does not give information on the batch of medicines reported with the complaint, the researchers weren’t able to determine the clinical significance of the problems.

But the prompting of a drug recall "can be regarded as a disastrous failure of the manufacturer’s quality plan," they noted.

The researchers pointed to Health Canada’s policies, which outline the regulator’s responsibility to monitor, assess the root cause of a problem and to conduct inspections to verify that corrective actions are implemented.

Surveillance tools working

A spokesman for Health Canada said when products are recalled or advisories or alerts are issued, it means its surveillance tools are working.

"It is true that the global drug supply chain has become more complex and stretches far beyond Canadian borders. Threats to the safety and quality of product distributed through the supply chain, include, but are not limited to the issues identified in the study such as substandard medicines," Eric Morrissette, a senior media relations adviser at Health Canada, said in an email Monday.

"It is difficult, however, to draw a direct correlation between the numbers of recalls Health Canada has communicated on during a period of time, and the overall quality of medicines on the Canadian market."

Morrissette pointed to contributing factors such as:

  • Improved detection of issues by Health Canada, such as the federal’s government adoption of Vanessa's Law, which, among other measures, gives the department the power to order a company to recall an unsafe product.
  • Changes to manufacturing practices, policies and oversight.
  • Health Canada’s increased efforts in openness and transparency, which may contribute to more risk communications being posted.

The British researchers also reported four incidents of falsified medicines — those where deliberate and criminal intent is involved. They said some falsified medicines may be intercepted or seized by enforcement officers on their way to target markets that aren’t necessarily intended for sale in Canada.

Other flaws identified by the researchers included packaging defects.