If you look at the Drugs.com link about Keppra in kiwi's post, you'll find "problems with walking or movement" listed as among the side effects you should report to your doctor.

"Numbness of the feet, hands, and around the mouth" is also listed as a common side effect that needs to be reported to the doctor. Problems with balance are also mentioned.

Although the neuro has said that the Keppra couldn't be causing this problem, it's possible that it could be causing it anyway.

Would it be possible to ask your doctor if it would be OK to try cutting out the Keppra for a while just so you can see if your foot symptoms get better without it?

I'm assuming that a doctor has checked any drugs you're taking to make sure that some drug isn't interacting badly with another.

Sometimes you have to tinker with drugs and their dosages until you figure out what is causing what, but every drug you take in can cause problems. Particularly if you're also taking other drugs.