A new book has revealed that Chevy Chase and David Spade tried to help Chris Farley overcome his drug addiction before he died.

The Last Days of Chris Farley, written by the actor's brother Tom and Tanner Colby, reveals that the pair were desperate to save their friend before he passed away from an overdose at the age of 33.

The Tommy Boy actor died after taking a "speedball", a combination of cocaine and heroin, in 1997.

Chase, who co-starred with Farley on Saturday Night Live, said: "[I told him] look, you're not John Belushi. And when you overdose or kill yourself, you will not have the same acclaim that John did. You'll be a blip in the New York Times obituary page, and that'll be it. Is that what you want?"

8 Simple Rules star Spade revealed that he was blamed for failing to prevent the death, saying: "I got a lot of s**t at the end about, 'Why weren't you there for him?' But being that close, I dealt with it all the time. And in that situation, before the guy's dead, he's just kind of an asshole.

"Truth is, you get a junkie who's wasted all the time and moody and angry and trying to knock you around, you say, 'OK, you go do that and I'll be over here.'"