Hi does topomax cause hair loss (thinning hair)? I was on it five years ago for migraine and most of my hair but unknown to me, I also had stage 3 thyroid cancer. I was treated for my cancer and anemia and have my hair back:) Once again, the doctor wants me on topomax for treatment of severe migraines. Hence, my question- was it the thyroid cancer, or anemia that caused the hair loss(almost baldness) or was it Topomax? Thank you kindly!