Nortriptyline is not in the same family, or classification of drugs as Topamax. There are other anti-seizure medications that you can take that work the same way as Topmax without the side effects.
- Gabapentin (Neurontin). Effective in preventing migraines, gabapentin's side effects include sleepiness, dizziness, diarrhea and mood swings.
- Lamotrigine (Lamictal). Rash is the most common side effect. Long-term use of lamotrigine can cause blurred vision.
- Tiagabine (Gabitril). Side effects include dizziness, fatigue, depression and confusion.
- Topiramate (Topamax). Also used to treat cluster headaches, topiramate can decrease the effectiveness of oral contraceptives. The drug also can prevent you from sweating and may increase your risk of kidney stones.
Neurontin has been great for a lot of people who can not manage the side effects of Topamax
Just some ideas, you may also want to visit my thread on medication and treatment options.