definitely make sure you do your research so you dont fuck up..... id say do around 600mg which is 2 bottles of robo max strength cough. make sure dxm is the only active ingredient/ inactives you dont have to worry about. also something i do is i try and eat a few peices of bread before drinking one bottle and i down it in moderations maybe 3 shots a bottle and then i eat some more bread if i can and repeat to make sure i dont puke it up and it has seemed to work well.