Now, however, the actor has shared a few more sobering updates about his health on Good Morning America. “My right side has completely stopped working,” he told the program. Dane said that he expects to lose control of the left side as well.

Dane -- who shot to fame amid six seasons on the hit ABC drama "Grey's Anatomy," where he played Dr. Mark Sloan, affectionately known as "McSteamy" -- said his symptoms began over one year ago, when he began to experience weakness in his right hand.

Eric Dane, an actor best known for playing Dr. Mark Sloan, aka "McSteamy," on "Grey's Anatomy," discussed his health challenges after being diagnosed with ALS.