well, First off, Make sire you get the Robitussin with the DM on the box.. very important. Ive done Dxm a few times and it always takes a while to hit, And usually before the trip kicks in i get really sick and nausiated. Thrown up like 4 of 6 times or so. The trip takes a while to kick in so be paitent.

I weigh 150-160 lbs, First time i took it i drank a 4 oz bottle of robotussin and ate 10 of the robo pills, Note - Didn't throw up doing that. Gave me a CRAZY trip and everyone there was really close to each other, i recomend that exact ammount =p