Chow, the NDP transport critic, said she was diagnosed with Ramsay Hunt Syndrome Type II after waking up with some discomfort on the left side of her face over the holidays.
Chow told reporters in Toronto Friday that she was prescribed a steroid, which she took for a week. The virus causing the disorder has been taken out of her system completely, she said, adding she is no longer taking medication and is not in any pain.
"The only thing that is not working well is that I can't smile in a balanced way," she said, adding her affliction was quite similar to Bell's palsy.
"But that does not stop me from working hard, pushing Stephen Harper for better investment in transit and infrastructure funding in this upcoming budget."
Chow said she called the news conference because "the House of Commons is going to start again in probably in two weeks or so … I want to get back to work immediately without having to explain many, many times about why I look slightly different."
Doctors have cleared her to go back to work, and she said she feels completely healthy.
The disorder, also known as herpes zoster oticus, occurs when the varicella-zoster virus, which causes shingles, spreads to facial nerves. The U.S. National Institutes of Health has classified the disorder as a "rare disease" and estimates it affects less than 200,000 Americans.
Chow noted that it could take weeks or even months to fully recover.
People encouraging Chow to seek mayoralty
Chow also hinted more strongly than she has in the past that she would consider a run for Toronto's mayoralty this year should current Mayor Rob Ford lose his bid to overturn a judicial ruling that he vacate his seat.
If Toronto council chooses not to appoint a successor, a byelection could be called, and Chow has been rumoured to be eyeing the city's top job.
"So as to what’s happening to the city of Toronto right now, Mr. Ford’s situation is still in front of the courts," she said, adding she would want to see what would come after Ford's appeal.
"I am seriously listening to people and when the time comes, if there is a decision, then I’ll consider what role I might play."
People are encouraging her to run, she said. "And then normally, I ask them what do you want your mayor to do? What kind of city do you want?"
She has previously said that she hasn't "shut the door completely" on a 2014 mayoral run, but until today had yet to clearly spell out her plans should a mayoral byelection be called.
"I don’t need my facial expressions to do my work," she told a reporter who asked if self-consciousness about her condition might affect her work in politics.
"You just have to get used to my face occasionally."