Lamictal and wt loss

my 13 yr. old daughter has been on 150mg. per day for about 9 months, have noticed major acne(cheeks,chin -very inflamed), huge wt. gain-from 92-134 lbs. in 6mo., she started her periods mid April and has had long periods with heavy bleeding and now for the second time in 31/2 months is anemic despite being put on birth control pills to stop the bleeding- she is exhausted-sleeping 12-14 hours per day-this is not her usual pattern.Previously thought her wt. gain was from Seroquel but even after being off it for 61/2 months there has been no wt. loss. The only other time she has had wt. gain with a med. is Tegretol- so maybe I shouldn't be suprised that she has this response to anothe AE.