Finance Minister Jim Flaherty has revealed he’s been battling a rare skin disease that's left him looking bloated and unwell in recent months.

In a statement issued by his office Thursday, Flaherty explained that for nearly a year, he’s had a condition called bullous pemphigoid. It’s a rare disease with no known cause that leads to blisters, rashes and lesions on the skin and mucous membranes.

He’s needed a strong steroid medication called prednisone to treat the symptoms, but the drug has caused his body to become bloated and his face to appear red and puffy.

The statement was issued after Flaherty revealed his condition in a candid interview with The Globe and Mail.

CTV Ottawa Bureau Chief Robert Fife says Flaherty’s appearance has been a hot topic of discussion on Parliament Hill for weeks.

“Everybody’s been talking about this for about two and a half months because everyone noticed that Mr. Flaherty was puffing up,” Fife told CTV New Channel Thursday.

“You might have noticed… in (the House of Commons daily) question period, when he stood up to speak on Tuesday, he was actually holding his stomach very tight.”

To calm concerns, Flaherty decided to go public with his diagnosis.

The 63-year-old MP for the Ontario riding of Whitby-Oshawa said he informed Prime Minister Stephen Harper of his condition and treatment just before Christmas and wants to assure Canadians that neither the condition nor the medication are affecting his ability to do his job as federal treasurer.

He told The Globe that he was reluctant to speak about his health to anyone.

"Most people are quite cautious about what they say, but a few people have said to me, 'Do you have cancer? ... What's going on? Are you going to die?' That kind of thing," he said.

"And, obviously, I am not. I mean, I will die eventually, but not over a dermatological issue."

Flaherty says the condition is already clearing up and he is hopeful his appearance will return to normal soon.

“Minister Flaherty will continue carrying out his day-to-day responsibilities and will not be commenting further on his condition,” his office said in a statement.

Dan Goodwill, chair of the Canadian Pemphigus and Pemphigoid Foundation, who told CTV’s Power Play he had endured a “similar illness” to Flaherty’s and was on prednisone for five years, suggested the treatment would not affect the minister’s job performance.

“It is a little bit difficult to deal with sometimes, but I went to work every day, and I’m sure he’ll be able to function fine and carry out his duties as best he can,” Goodwill said.

He added that in roughly 80 per cent of those afflicted with the disease it takes “a matter of months to a few years to solve,” while in a small percentage of people the illness becomes more chronic.

Treasury Board President Tony Clement told reporters Thursday that he thinks that there are some parts of ministers’ lives that should not be open to media attention.

"I think as long as we feel we're doing our jobs, there is a part of our lives that should be private and personal. I know there are some in the media and other commentators who may disagree with that. But look, I think he's doing a great job and he continues to do a great job for years to come,” he said.