Be a good friend and call him, and if he doesn't answer call the suicide hotline or his parents. Call him up, talk to him, don't try to get him to laugh like the kids up there said. If he's actually considering taking his own life, then laughter isn't what he needs right now. Just tell him that you care about him, and that he shouldn't commit suicide because not only will it devastate his family, but also you. Take everything he says seriously, and open up. Just don't joke around or try to get him to laugh or shit, that will only bottle him up. But seriously, call him, and if he doesn't answer then find the suicide hotline number. Think about it, if he killed himself, would you want to know that you could've prevented it, but didn't because you were afraid that he would get angry because you called the number. Stop at nothing to make him know that you care, and if that doesn't work, just keep him alive.