At 6 months old my son was on 1/2,1/2, & 1 tablet.  He started doing the same thing.  After 6 months of waking only once for a feed he was waking up to 5 times a night.  I'd breast feed him for 2 and bottle feed him for 3 with him finishing the full 240mls each time!  During the day he wasn't too bad as I pout it down to only being the half tabs during the day.  His levels were too high when his bloods were done so we dropped it back to 1/2 tab x 3 and he went back to once a night after about a week afer the decrease.  He's still on 3 x 1/2 tablet and has finally stated sleeping thru the night.(at 16 months, he's now 18 mnths).  i don't know if it will be the same in your childs case but it's good your getting the bloods done so soon anyway.  Hang in there I know how you're feeling.  I did the 5 times a night for about 6 weeks before the bloods were done and the results in.  It was frustrating though as I knew the problem was probably the meds!

Take care and try and catch some zzzzz during the day.

Lisa D