An overdose of topiramate can occur if someone takes more than the recommended dose or if they take it in combination with other medications or substances that interact with it. Symptoms of an overdose can include dizziness, confusion, loss of consciousness, seizures, and respiratory depression, among others. In severe cases, an overdose of topiramate can be life-threatening. If you or someone you know has taken too much topiramate, it is important to seek medical attention immediately.