I take 360mg a day, all at once at night. I also don't know of any at home test, although wouldn't it be great?

I'm wondering how you're cutting the Dilantin pills in half. Mine have always been time-release caps with big warnings not to open them up.

Or - is your husband taking generic phenytoin and not brand name Dilantin? Then that would explain the changing blood levels, since the generic have a wider range of actual chemicals within the dose itself.

Quote from Art_930:

Or - is your husband taking generic phenytoin and not brand name Dilantin? Then that would explain the changing blood levels, since the generic have a wider range of actual chemicals within the dose itself.

That must be it because that is what he takes. It's in a caplet but when you open it up the pill is inside and that's how he's able to cut it in half. He's felt fine today so guess we'll just have to see.