The former Two and a Half Men actor Charlie Sheen has offered personal details about his HIV treatment.

Tuesday morning on The Today Show, troubled actor Charlie Sheen sat down with Matt Lauer to confirm what his rep announced yesterday: He is HIV positive.

“I’m here to admit that I am, in fact, HIV positive,” Sheen says in the interview; the 50-year-old actor has been living with the diagnosis for “roughly four years.”

“It started with … this series of crushing headaches and insane migraines and sweating the bed, completely drenched two or three nights in a row, that I was emergency hospitalized,” Sheen recalls. “I thought I had a brain tumor, I thought it was over. After a battery of tests and spinal taps — all of that crap — they walked in the room and said, ‘Boom, here’s what’s going on.'”

Sheen further claims that his (very public) drug abuse and downward spiral was brought on by his HIV diagnosis. “I was so depressed by the condition I was in that I was doing a lot of drugs, I was drinking too much and I was making bad decisions,” he says.

Although, speaking about his public meltdown and online rampage in 2011 (during which he coined the term “winning”), Sheen says, “I wish I could blame it on [the diagnosis] – that was more roid rage.”

The reason he is going public now, Sheen explains, is “to put a stop to this onslaught, this barrage of attacks of sub-truths and very harmful and mercurial stories threatening the health of so many others.”

When asked if he’s been paying former sexual partners and confidantes to stay quiet, Sheen says, “Not after today I’m not. That’s my goal. That’s not my only goal.”

“I think I released myself from prison today,” Sheen adds, referring to the people who have allegedly been extorting him for money.

The actor adds that it is “impossible” for him to have transmitted HIV to any of his sexual partners. He is “not entirely” aware of how he himself contracted the virus.

To read more about HIV treatment and prevention, visit AVERT.org and AIDSMap.com.