James Franco is too busy to take drugs.

The 'Howl' actor admits people have huge misconceptions about him because of the characters he has played in his movies - mainly gay men or people with drug habits - and insists he is nothing like his on screen alter egos.

He said: "Everyone thinks I'm a stoner, and some people think I'm gay because I've played these gay roles. That's what people think, but it's not true. I don't smoke pot. I'm not gay. Why don't I drink or take drugs? No time, really."

Despite the constant speculation about his sexuality, the 32-year-old star - who has been in a relationship with actress Ahna O'Reilly for five years - insists if he was homosexual he would be open about it.

He told gay magazine The Advocate: "I'd tell you if I was. I guess the reason I wouldn't is because I'd be worried that it would hurt my career. I suppose that's the reason one wouldn't do that, right? But no, that wouldn't be something that would deter me. I'm going to do projects that I want to do."

James has played gay or bisexual characters in 'Howl', 'Blind Spot' and 'Milk' and has adapted two gay-themed poems for student films and he claims he finds it more "interesting" to portray same-sex relationships on the big screen.

He explained: "In this history of cinema, there are so many heterosexual love stories. It's so hammered, so done. It's just not that interesting to me. It's more interesting to me to play roles and relationships that haven't been portrayed as often."