I was on topamax for several months and never did get any good results. I still take zomig and fioricet for mine. So far for me no preventive has worked and over the years I have tried so many I can't even remember but once I see the name I recall it. Topamax was the last one I tried. My migraines don't seem quite as intense now that I have been taking B2, B6 and Magnesium. I've noticed a decline in what I've been taking. That's a good thing. I was taking Demerol as well but haven't had to use any for about 3 weeks now.
I hope the Topamax works for you soon. I hate all the side effects to all those preventives but if something works it's well worth it and the side effects usually diminish with time anyway.
Take care and feel better.
Diane