The Chalk River nuclear reactor, located 180 km northwest of Ottawa, is producing 35 to 40 per cent more isotopes than usual to compensate for the crunch.
"It's like anything else, it's market demand," said Dale Coffin, a spokesperson for Atomic Energy of Canada Ltd., which runs Chalk River.
"We're not only producing for North America, we're producing for global demand."
Medical isotopes are radioactive material that can be used to scan the body for tumors and other illnesses, or to treat cancer through radiation therapy.
Last week, Health Canada warned that the international supply of isotopes might be smaller than usual, possibly because a nuclear reactor that produces them in the Netherlands is temporarily closed. Chalk River first increased its production in September in anticipation of the shortage.
The Chalk River reactor itself wasn't producing isotopes for six-and-a-half days recently when it was shut for routine maintenance and a research project. The shut down, however, wasn't expected to hurt isotope supplies, as the reactor regularly produces nearly seven times the amount of isotopes required by the Canadian market.