Aglukkaq, the federal health minister, said banning a single drug won't solve the problem of prescription drug abuse, she warned.
"Banning a generic version of one drug would do little to solve the actual problem," Aglukkaq said her letter. "There are almost 100 authorized drugs in Canada that are in the very same class of drugs as OxyContin.
"Banning all these drugs because they have the potential to be addictive would help dry up the drug supply for addicts, but would lead to pain and suffering for patients who desperately need them."
Opposition Liberals accused the minister of abandoning her responsibility to prevent prescription drug abuse.
"It's a serious epidemic," said Liberal aboriginal affairs critic Carolyn Bennett. "Why will she not listen to the health ministers of this country?"
Aglukkaq says Ottawa will tighten licensing rules so that distributors of oxycodone have to keep better track of where the drug goes. Starting in 2013, they will need to report spikes in sales and changes in distribution patterns, in addition to previous responsibilities to report losses and theft.
And if the provinces eventually find that they still can't sufficiently control oxycodone, Aglukkaq says she would be open to new regulations to further restrict prescribing and dispensing of the drug.
David Juurlink, the head of clinical pharmacology at the University of Toronto, said he'd like to see federal action on the drug as soon as possible. If Ottawa sees legal barriers to banning oxy, it should at least consider changing the law, he said.
Canada's doctors should be warned against prescribing high doses of oxycodone over a long period of time, Juurlink said, because OxyContin is among the easiest medications to abuse and is "actually very dangerous."