Charlie Sheen has revealed he is HIV positive.
The actor made the admission in an interview on NBC's Today show.
It comes after Hollywood was rocked by rumours a high profile star had the illness and may have passed it on to several A-listers.
The former Two and a Half Men star said he was speaking out to dispel the "barrage of attacks" and "sub truths" and hopefully help others with the condition come forward.
He revealed he was diagnosed with the illness four years ago after suffering a series of cluster headaches and "insane migraines".
"I thought I had a brain tumour. I thought it was over. After a battery of tests they walked into the room and told me what was going on.
"It's a hard three letters to absorb. It's a turning point in one's life."
Sheen admitted he had paid various people millions of dollars to keep quiet about his illness up until now.
"What people forget is that is money they are taking from my children. I've got five kids and a granddaughter," he said.
The actor said it was true one prostitute came over to his house, saw his HIV medication and threatened to expose him if he didn't pay her off.
Asked if he was still paying some of these people, Sheen replied: "Not after today I'm not. I've released myself from my prison today."
Sheen said it was "impossible" he could have passed the disease on since his diagnosis in 2011 as he had been upfront with all his sexual partners.
Of the two people he did have unprotected sex with, he revealed they were under the care of his doctor and were fully aware of the risks.
Asked if he knew how he contracted the virus, he said: "Not entirely."
He added: "I don't feel any stigma about it anymore. I have a responsibility to better myself and to help a lot of other people.
"And hopefully with what we're doing today, others may come forward and say, thanks Charlie, thanks for kicking the door open, you know."
Sheen also revealed:
At the moment he has an undetectable level of HIV in his blood thanks to medication
His condition has not developed into AIDS, as has been reported by some media
He has to take four pills each day and has never once missed his medication
He admitted he was still drinking "a little bit" but is off drugs