I had this s/e at 100 mgs, but not at 50 mgs. I drink lots of water and exercise fairly regularly. Don't know for sure, but I suspect lowering the dosage and these other two factors all combined made the difference. Hang in there...I have found Topamax to be the only effective thing w/ reference to cutting back on my migraines. The s/e's are kinda "tricky," so it requires lots of patience on your part and that of your physician.