The alert from the Office of National Drug Control Policy was sent out after Health Canada gave six generic pharmaceutical companies the licence to begin manufacturing the drug, which was produced until earlier this year under the brand name OxyContin.
The U.S. alert states, "The potential exists for diversion into the United States because the old formulations, which are easier to abuse, are unavailable in the United States. This alert seeks to raise awareness of this change with the law enforcement along the Northern Border so law enforcement and border officials can work jointly to prevent diversion."
OxyContin was pulled from the market by its manufacturer earlier this year over concerns about abuse of the drug.
The company issued a reformulated version called OxyNeo that it says is less susceptible to abuse, but with the expiry of its patent for OxyContin in late November, generic drugmakers are now able to manufacture the original drug.
Federal Health Minister Leona Aglukkaq refused to block generic manufacturers' applications to produce oxycodone, but did announce new restrictions for the drug that will force manufacturers and pharmacists to notify Health Canada when there are any spikes in sales.
The U.S. drug control agency notes this change in its letter to border officials, adding that Canada is taking steps to deal with abuse of the drug.
Liberal MP Carolyn Bennett said the government's decision on generic OxyContin could affect traffic at the border.
"I think when there's an alert like this then all of a sudden the officers are on the lookout, they profile, they have a look. And yes, this could be a big problem at the border if indeed they're going to try and stop all of this, they know is readily available in Canada or will be," said Bennett.
The health minister has been under increasing pressure lately, from provincial health ministers, opposition politicians, police forces and aboriginal groups, to either reverse her decision or delay the release of the drug into the marketplace.
New Democrat health critic Libby Davies wants Aglukkaq to meet with her provincial counterparts to deal with the growing concerns.
"I think what is absolutely essential is for this federal health minister to sit down with provinces and work out a solution. Because I think they can work out a solution if there's a political will to deal with it. That's step one, but that's not happening."
Aglukkaq has said frequently in Parliament the decision to allow the generic version was made by scientists, and she doesn't want to interfere politically in these kinds of decisions.
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