Charlie Sheen has credited an experimental anti-HIV drug for helping him ward off “borderline dementia,” throwing his star power behind the drug in an effort to help get it approved for wider use.

The actor spoke at an awareness event in Hollywood last night for PRO 140, an injectable therapy for HIV patients being marketed by Vancouver, Wash.-based biotechnology company CytoDyn.

Sheen, who revealed that he was HIV positive in November 2015, told the crowd of 300 gathered at the Hollywood Roosevelt that he was previously taking four pills daily as part of his “cocktail” of drugs, but suffered from serious side effects as a result. “[The drugs] kept me suppressed and alive,” he said, “but I struggled with a constant migraine and at times, borderline dementia.”

Sheen was first introduced to PRO 140 on the Dr. Oz show last February, when CytoDyn’s CEO appeared on the talker to offer to enroll the actor into a clinical trial of the injectable drug.

According to CytoDyn, PRO 140 functions as an antibody to reduce or control the HIV viral load in subjects. Since the treatment is injected into pockets of fat, Sheen joked “there’s a lot of opportunities” when administering.

Still, he stressed that he has felt “no side effects” from the treatment, adding, “I’ve started to feel back to myself again and back in touch with all aspects of my life.”

“When I was first diagnosed, I knew it wasn’t a death sentence but it was just a giant frickin’ bummer,” the actor revealed.

The actor also tipped his hat to his “compassionate” doctors, and vowed to use his name to back the treatment and get it out into the marketplace.

“I accept the gift of being alive,” he said in his closing remarks. “I could run and hide from this whole thing and not be outspoken and honest and open about it, but I’ve chosen a path that’s the opposite.”