UPDATE: Conaway's rep, Phil Brock, tells E! News: "He is still unconscious, ventilated and intubated. No improvement at all today."
Brock also confirmed that Conaway has pneumonia and sepsis.
"He was found unconscious with pain killers and cold medicine in his system to my knowledge...my assumption that the combination of pain killers and cold medicine led to his not knowing how seriously ill he was. If he was not taking any medicine, he wouldn't have passed out and would have gone to a doctor or a hospital on his own. If you have been an addict, any medicine is too much, so it can be deduced that it's some type of O.D."
Things aren't looking good for Jeff Conaway.
"He is not getting better," a source close to the former Taxi star tells E! News. Conaway was hospitalized a week ago for what was originally believed to be a prescription pill overdose after he was found unconscious at home.
Dr. Drew Pinsky, who treated Conaway on Celebrity Rehab, later clarified that the 60-year-old actor was suffering from pneumonia and sepsis, a possibly deadly blood infection, and was in a medically induced coma.
And Conaway remains in critical condition...
"He was excessively using prescription meds," the insider says, echoing what Conaway has talked about many times over.
Conaway told E! News last year that he was taking up to 54 OxyContin pills a day, saying that he had "a strong constitution."
"It takes a lot to put me down," he joked.
Meanwhile, ex-girlfriend Vikki Lizzi posted a video on Facebook of the two of them singing together at a charity event in December.
"Our last performance together...'I Got Love' which we co-wrote together and his inspirational song 'Heal Me.' Sending powers to Jeff through St Jude, the worker of miracles," Lizzi wrote.
The estranged pair filed dueling restraining orders earlier this year, but we hear that Lizzi has been trying to get legal permission to visit Conaway in the hospital.
(Originally published on May 24, 2011 at 4:45 p.m. PT)