Finance Minister Jim Flaherty normally keeps pretty quiet about his personal life, but said recent questions about his changing appearance have forced him to go public with his struggle against a rare skin disease.

In an interview with The Globe and Mail, Flaherty, 63, said he has a rare skin disease called bullous pemphigoid.

The condition causes blisters on the skin and inside the mouth, larynx and nasal cavities.

The treatment includes strong steroid and the side effects include weight gain, facial swelling and difficulty sleeping. The disorder has also affected the quality of this voice. Listen to his interview with Bloomberg from Jan. 25.

The Whitby-Oshawa MP said he’s going public to assure Canadians that he’s still able to do the job as finance minister.

He said people have been asking him what’s wrong and if he has cancer.

Flaherty said he informed Prime Minister Stephen Harper before Christmas.

The Globe reported the disease is so rare there are no Canadian statistics.

There’s no known cause, but with treatment most patients will enter a partial remission in two to five years.