um, she is 8 yr. and weighs 48 pounds? wow. i have adhd (attention deficit hyperactivity disorder), and im 12. i weigh like 90 or less pounds. well, does she eat food? because i weigh 90 pounds, because i dont eat alot. that could be why she weighs so little.
Kind of need more information. Is it an extended release or an immediate release? One dose of 30mgs or several doses of a smaller amount? I do think a single dose of 30mgs in either a XR or immediate release would be a lot.
However, what matters the most is how it works for her. There is always a bit of trial and error by the doctor and they depend on the parents to inform them how the meds are working. Have you tried smaller doses? Do the doses make her spacey? How long has she been on the dose? Actually, what matters the most is that you and your doctor communicate on how the meds are affecting your daughter. Best wishes.