If I were writing it, I would probably not slur the sounds, but maybe indicate through syntax, grammatical errors, groping for the right word, saying silly things, etc. It's been a while since my college days, so I can't think of any examples off the top of my head of drunken speech. But then again, it depends on the character. Some people almost sound more well-spoken when drunk, some wax philosophical, while others get downright goofy. I think if you show a change in speech that is different in some way from how the character usually talks, and then indicate that they are drunk, it could be sufficient.