given that this is almost certainly a symptom of anxiety - you're not having a seizure, you've had tests that would tell you if something was wrong that might cause them! - I wonder if you've tried a course of CBT, or cognitive behavioural therapy?
Medications are often more a means to a solution than the solution themselves. CBT looks at changing the way we think and feel about things, helping us to better analyze and understand our symptoms. Ask your therapist, and get their opinion, but I honestly think it could be a great help to you :)