Val Kilmer appeared to be struggling to speak as he made his first public appearance since denying reports he has cancer.
His friend Michael Douglas had claimed Val has the same tongue cancer he had been diagnosed with, something Val has denied.
Video footage of the Batman Forever actor presenting the film version of his one-many play Citizen Twain in Los Angeles shows Val slurring and dabbing his mouth with a tissue.
Val has previously told fans Michael had been "misinformed" about his condition and added he has not spoken to the star for nearly two years.
Michael, who was diagnosed with tongue cancer in 2010 and was given the all-clear the following year, said his friend was "dealing with exactly what I had", adding: "Things don't look too good for him."
He said: "My prayers are with him. That's why you haven't heard too much from Val lately."
But Val, 56, who worked with Michael on the 1996 film The Ghost And The Darkness, assured fans in a lengthy Facebook post that he is not suffering from cancer.
The footage of Val introducing his film shows the actor telling the crowd he had to cancel his upcoming tour for the play because his "tongue swelled".
He said: "I went into rehearsals down in Florida and started having trouble with my speech. Obviously I'm still recovering. My tongue swelled up and I cancelled the tour. As I'm recovering, I'm showing this."