Actor Jeremy Piven said Monday at the Golden Globe Awards that his decision to abruptly leave the Broadway revival of "Speed-the-Plow" because of mercury poisoning was "a completely humbling experience."
Watch Jeremy Piven's exclusive interview with "Good Morning America" Thursday morning between 7 a.m. and 9 a.m.
Piven, a Golden Globe nominee for his role on HBO's "Entourage," departed the starring role in the critically-praised production of David Mamet's comedy Dec. 18, less than two months after the show opened in New York. The actor said he had mercury poisoning, which left him too fatigued to keep up with the demanding role. The poison claim was met with skepticism from many.
Piven will appear in his first sit-down television interview Thursday morning on "Good Morning America" to tell his side of the story.
Dr. Carlon Colker, the primary internist treating the "Entourage" actor, detailed his debilitating condition.
"This is a situation of mercury toxicity," Colker, the medical director of Peak Wellness of Greenwich, Conn. (and a champion competitive bodybuilder) told ABCNews.com. "His level [of mercury] was quite high, almost six times the normal limit. ... In this case, it's either because of fish -- he ate sushi twice a day for years -- or because of the Chinese herbs he was taking, or both. We're pretty sure about the fish, how much the Chinese herbs contributed, we don't know. We don't have the specifics of which herbs he took."
"Right now he's being treated with bed rest; out of bed is tolerated," Colker continued. "He spent three days in the hospital, he's been discharged. He was seen by a Yale cardiologist and a professor emeritus of neurology. He's on some dietary supplements as well to protect his organ system function and to clear the mercury from the body. He also cannot eat fish."
"He'll be OK. I think it'll take a few weeks to a couple of months," Colker concluded. "Unfortunately it was like pulling teeth to get him out of the show. This is a situation that I think will resolve as long as he's attending to his health."
Piven's abrupt departure from "Speed-the-Plow" was a move deserving of its own "Entourage" episode.
"We have been advised by Jeremy Piven's medical representatives that he is seriously ill and is unable to fulfill his contractual obligation to 'Speed-the-Plow.' Consequently, he has left the production ten weeks early," the show's producers said in a statement to ABCNews.com.
In an interview Wednesday with Daily Variety, Mamet took an irreverent tone.
"I talked to Jeremy on the phone, and he told me that he discovered that he had a very high level of mercury," the playwright told Daily Variety. "So my understanding is that he is leaving show business to pursue a career as a thermometer."
According to the EPA, the most common way people ingest mercury is by eating fish containing methylmercury (most often tuna or swordfish) or by breaking products containing elemental mercury (like, as Mamet suggested, a thermometer).
Mercury is one of the most dangerous toxins on earth. The amount of damage it can do to a person depends on when the person is exposed (as a fetus, child or adult), the type of exposure (whether it's swallowed, touched or inhaled) and the length of the exposure.