Canadian OxyContin prescribing increased dramatically near US-Canada border following introduction of tamper-resistant formulation in US: study

13/11/2012

Canadian OxyContin prescribing rose substantially near a major international border crossing immediately following the introduction of a tamper-resistant formulation in the United States, according to new research conducted at the Institute for Clinical Evaluative Sciences (ICES).

“There is only one plausible explanation for this finding, and it’s the diversion of huge quantities of the original OxyContin formulation from Ontario into the United States,” says Dr. David Juurlink, co-author and ICES scientist.

OxyContin is a powerful painkiller, made to slowly release the potent opioid oxycodone to treat patients who require a continuous, around-the-clock opioid analgesic for management of their moderate to severe pain for an extended period of time. Addicts break down the coating of the tablets and mix them with water in order to inject or snort the crushed pills to get an instant high.

In August 2010, a tamper-resistant formulation of controlled-release oxycodone (OxyContin-OP) was introduced in the United States but not in Canada. OxyContin-OP has a new tamper-proof coating which, to prevent abuse, turns to gel when it is mixed with water.

The population-based, serial cross-sectional study examined retail pharmacies in the three cities in Ontario with the highest volume of US-Canada border crossings in 2011 and found:

A 390 per cent increase in OxyContin dispensing from pharmacies close to the Detroit-Windsor Tunnel.
Almost 250,000 excess OxyContin tablets were dispensed in Windsor near the Detroit-Windsor Tunnel between August 2010 and October 2011.
OxyContin dispensing near border crossings in Niagara Falls and Sarnia remained stable.
Following warnings to prescribers and pharmacies regarding drug-seeking behaviour in April 2011, dispensing declined and by November 2011 had returned to baseline rates.

“These results are a testament to the abuse potential of OxyContin, and they have immediate implications for government policy and public safety. If the generic formulation of the original product is allowed on the Canadian market, I predict we will see a flood of the product back onto the streets, not just in Canada but also in the USA,” says Tara Gomes, lead author and ICES scientist.

The results of this study highlight the impact that differing availability of opioids may have on trafficking across borders, and also suggests that timely notification of prescribers and dispensers of this drug-seeking behavior may help mitigate the problem.

Authors: Tara Gomes, J. Michael Paterson, David N. Juurlink, Irfan A. Dhalla MD, Muhammad M. Mamdani.

The study “Reformulation of OxyContin and pharmacy dispensing patterns near the US-Canada border,” is in the November 13, 2012 issue of Open Medicine.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.