Does Canada not profit or break even on sale of drugs?
Ensuring access to those who need it is the primary concern. If Americans were suffering an unintended shortage, that'd be one thing... But causing an artificial shortage for Canadians in order to profit off Americans would result in near immediate regulation.
In almost all of the systems, medication is not covered unless you're a child, extremely poor, or very old.
In practice about 30% of all healthcare expenditure in Canada comes from private sources, since things like medication, dental care, vision care, and a whole myriad of other critical segments of healthcare are not covered by any government health plan.