Hi deerhunter,
The dizziness and tiredness that you are experiencing are quite common in regards to Keppra(and our other anti-seizure meds). These feelings should pass once the body accepts this switch.
Are you being totally removed from Dilantin? If so, is this a sudden elimination or a weaning off? Your feelings could also be the result of the two meds counter-acting against each other.
Are you keeping a notebook about these feelings? Also, during a switch/elimination period, seizure activity can occur. The body is simply reacting to the absence/lower dosage of the one being removed.
If these feelings persist or get stronger, talk with doc immediately. I was on a med that had me feeling this way for two years. I hated it!!!! It made me feel unsafe about leaving home until that morning dosage was slept off.
You've been on Dilantin for a long time. This is a big change for you, physically and emotionally. Hang in there and give this change some time to see if these feeling subside. Do stay on the alert for anything unusual(double vision, bladder control, poor concentration, etc)
I have been taking Keppra since the 90s. I currently take Keppra XR along with oxcarbazepine(trileptal).
Wish you the best ,
angie