Charlie Sheen's Doctor Says Actor Has an Undetectable Level of the Virus in His Blood

The fact that Charlie Sheen is HIV positive is not going to shorten his life, according to his doctor.

Following the 50-year-old actor's admission on theToday show on Tuesday that he was diagnosed roughly four years ago, his doctor, Robert Huizenga -- who The Biggest Loser viewers will recognize from his role on the show -- is also speaking about Sheen's health. Huizenga, an associate clinical professor of medicine at UCLA, said the former Two and a Half Men star's HIV viral blood levels have dropped to undetectable due to taking his medication consistently.

"Four years ago, Charlie Sheen came to see me with an upper viral infection followed by joint aches, swallowing complaints and then progressive severe headaches," Huizenga said in a statement to ET. "During this infection, his HIV tests 'seroconverted' (acutely changed) from negative to positive. He was immediately placed on four antiretroviral drugs and his HIV viral blood levels thankfully dropped to undetectable. He has tolerated his antiretroviral cocktail and by faithfully complying with the daily pills, his viral HIV load has remained consistently undetectable."

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"With Charlie remaining dedicated to his treatment regimen, I expect the HIV will only minimally -- if at all -- affect his predicted life expectancy," he added.

On the Today show, Huizenga also stressed that Sheen did not have AIDS.

"AIDS is a condition when the HIV virus markedly suppresses the immune system and you are susceptible to rare difficult cancers and infections. Charlie has none of those," he told Matt Lauer. "He is healthy. He does not have AIDS."

Huizenga revealed that his biggest concern for Sheen is actually his "substance abuse and depression," rather than the virus itself. The doctor admitted he was "petrified" that Sheen would not take his medicine, however, the actor claimed that he has never missed his medication once.

"We’re petrified about Charlie," Huizenga said bluntly. "We are so, so anxious that if he was overly depressed, if he was abusing substances, he would forget these pills, and that's been an incredible worry. But magically, somehow in the midst of personal mayhem, he's managed to continue to take these medications."

For his part, Sheen said he still drinks, but no longer does drugs.

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Huizenga praised Sheen for coming forward about his diagnosis.

"I anticipate Charlie can save many more lives coming forward with his revelation then I could ever have aspired to as a doctor," he said in his statement.

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