I tried three different medications before I found one that controlled my seizures. There is no magic way to know which medication will work for a specific person. Although it feels frustrating to be switched from one medication to another, it is a good medical decision to keep trying to find the antiepileptic drug that best controls seizures with the least side effects. Keep in close contact with your nurse and doctor to be sure they understand your response to medication. That's a good question.
All medications can cause side effects.
However, most people tolerate their medications very well, The best way to tell if you are having side effects is to notice any symptoms you feel when you first take a medication or when the dose has changed. Some side effects of seizure medication are symptoms you feel, and are related to your dose of medication. If you are taking more medication than you can tolerate, you may feel groggy, or dizzy or sick to your stomach. You may have poor balance or see double at times. The dose at which these symptoms occur varies and some people can tolerate a much higher dose than others.