(Photo credit: Evan Agostini/Invision/AP Photo)

Michael J. Fox revealed in 2000 that he had Parkinson's disease, and the diagnosis was traumatic, to say the least. However, after he began seeing a therapist, the actor told Howard Stern that his marriage to wife Tracy Pollan "got great."

Plus, "Sex is great," he revealed on Wednesday. "I always say, the only thing about sex is deciding who's going to be the agent of motion!"

Michael J. Fox Opens Up About Parkinson's Diagnosis

Fox, 52, now stars in a new Fox series, "The Michael J. Fox Show," which is loosely based on his life. And though he's experiencing great success these days, he admitted to Stern that life after his diagnosis was rocky.

"It just felt helpless," he admitted. "It just felt unfair in a way. … But it's hard to explain."

To cope, Fox said he began to self-medicate.

Stars Shed Light on Parkinson's Disease

"My first reaction to it was to start drinking heavily," he said. "I used to drink to party, but now I was drinking alone and … every day."

After a year of what he describes as "a knife fight in a closet," he sought professional help and "it all started to get really clear to me."

"It's just, take one day at a time," he said. "Then things started to really turn the other way."