Splitting Doses | ADHD Information

My dd was just diagnosed with ADHD last week and through the Thanksgiving weekend we tried Medadate (sp?) which made her very aggressive and weepy, so tomorrow we are trying Vyvanse, but my doctor told me to split the capsule and only give her half.  Has anyone else split capsules for ADHD before?  I am assuming that my doctor told me to do this because she was on the lowest dose of Medadate and this is the lowest dose of Vyvanse and he wants to see what will happen...any thoughts?  This is a whole new world to me (despite the fact that I am a teacher...it is very different when it is your own child that you are dealing with), so if anyone has any suggestions I am open to anything. I have had success with splitting my son's dose of vyvanse with a method recommended by several doctors.  He was given the smallest dose which was too high for him and was told to split it in half.  The method was one with which I was not familiar.  I think the lowest dose is 30mg.  Disolve whole contents of capsule in 2 ounces of water ( I mark a glass used solely for dispensing his meds & mark the side with perm. marker) Pour out 1 ounce and have him/her drink the remaining.  I know it sounds complicated, but it's amazing how you get used to the routine.  It's worked wonders for him.  He's tried several meds and this one has worked quite well so far with minimal side effects.  Good luck and feel free to ask any other questions.