What Is The Dosage Of Depakote?

my daughter has been diagnosed with bipolar and is taking Depakote 1000mg once a day and shes been extremely drowsy so the nurse said to bring the dose down to 750 mg once a day but I thought she should maybe just take 500mg and she did for the past 3 days has only taken 500mg and she hasnt been doing to good she said she doesnt feel good and is also drowsy not as much as before but has alot of anxiety did we make the mistake of lowering it too much