A Child, Dwayne, Has Recently Started on Carbamazepine to Treat

A child, Dwayne, has recently started on carbamazepine to treat seizures. He comes to see you and you note that while his carbamazepine levels had been in the therapeutic range, they are now low. The possible cause for the low carbamazepine levels may be:

A) Dwayne hasn't been taking his carbamazepine because it causes insomnia.
B) Carbamazepine autoinduces metabolism, leading to lower levels in spite of good compliance.
C) Dwayne was not originally prescribed the correct amount of carbamazepine.
D) Carbamazepine is probably not the right antiseizure medication for Dwayne.