I am now on 300 mg daily (100 mg in AM and 200 mg in PM). I take it for severe vertigo which occurs without warning.My neurologists best definition is "migraines without pain". I had an episode in 2006 and unfortunately was standing next to a concrete sidewalk. The result was a fall with a fractured humerus requiring surgery and physical therapy x 6 weeks. My Zonegran was recently reduced from 200 mg twice dailyto current dose due to side effects of eye twitching (L eye only) and tingling/numbness of legs/hips. I also have decreased concentration, difficulty with word finding, etc. Anyone else have an experience like mine?