Jeff Conaway, 'Taxi' star and onetime 'Celebrity Rehab' patient on Dr. Drew Pinsky's reality series, has been visited in the hospital by his former sobriety coach.

As the troubled 60-year-old actor fights to survive, Pinsky denied that Conaway's substance abuse was behind reports of a coma.

On Friday, the doctor tweeted: "Just visited Jeff Conaway. He is stable & looks like he will recover from his pneumonia....Not an OD, like press is alleging & certainly not dead." He also criticized Conaway's manager for asserting that Conaway was comatose, when in fact, according to a Pinsky tweet: "He's in an induced coma...a Propafol drip."

However, in his most recent updates, Pinsky takes a more dire tone about the 60-year-old's condition, telling Twitter followers on Saturday the actor was "not doing well today suddenly."