You really do have to ramp up on the anti-seizure meds slowly, but I doubt that half a pill (100 mg, right/) would be enough to be harmful. But -- you are having some pretty nasty side effects. That's why they start with a low dosage and gradually up it -- to keep the amount of side effects down. Maybe you can call your doctor and get your appt. moved up a day or two. I feel for you with that relentless pain. We all do.

Mary