"Mr. Speaker, let me begin by saying on behalf of all of us in the House, we wish the minister of finance well and a speedy recovery," NDP finance critic Peggy Nash said to rousing applause during question period.
Flaherty — whose marked weight gain and puffy face had been fuelling rumours on Parliament Hill — decided to go public in the Globe and Mail after fielding questions from colleagues and others about his health.
"Minister Flaherty has disclosed that he is undergoing treatment for a non-life-threatening, but serious dermatological condition known as bullous pemphigoid," spokesman Dan Miles said in an email.
Bullous pemphigoid is a rare blistering skin disorder that can produce lesions on parts of the body.
Flaherty, 63, has been prescribed a steroid called prednisone to help clear up the condition, which carries with it side effects such as bloating, weight gain and redness of the skin. It's also possible that Flaherty may suffer from bouts of sleeplessness as a result of taking the drug.
"The minister says the condition is clearing up and he is hopeful his appearance will return to normal in the near future," said Miles, repeating Flaherty's own insistence that the treatment won't affect his ability to do his job.
"Minister Flaherty will continue carrying out his day-to-day responsibilities and will not be commenting further on his condition."
Asked if he knew why it took Flaherty so long to make his condition known, Treasury Board President Tony Clement defended his fellow minister, saying that he has a right to keep his health condition to himself.
"As long as we feel we're doing our job, then there is a part of our lives that should be private and personal," said Clement, who added that circumstances would be different had Flaherty been unable to carry out his duties.
"If you are debilitated, that kind of would be noticed, and there would be a legitimate question," he said. "But that is not the case here."
In the Globe interview, Flaherty said he informed Prime Minister Stephen Harper of his condition and treatment before Christmas.
The minister's cabinet colleagues were quick Thursday to wish Flaherty a full recovery.
"I was very pleased to learn that his condition does not in any way impact his ability to do his job or to fulfil his commitment to Canadians," said Heritage Minister James Moore.
Opposition MPs also expressed their support.
“Wishing Jim Flaherty a speedy recovery,” interim Liberal leader Bob Rae wrote on Twitter. “Glad it’s not more serious,” chimed in NDP House leader Nathan Cullen.
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