My 16 Year Old Son Is Taking Intuniv He Just

my 16 year old son is taking intuniv he just started it along with focalin er. he was told to take it at bedtime. I am a little worried about the side effects and why at night and not in the morning with the focalin ? he started with 1mg and now 2 then 3 in the pm. Can this be dangerous or lethal taking it at bedtime ? i'm very concerned &worried.