My sister in law has been taking topamax for at least two years n...

My sister in law has been taking topamax for at least two years now for migraines, I think 50mg a day. She has developed serious issues, which she nor her doctors believe is from the drug. She has back pain, moodiness, sleeplessness, extreme muscle cramping. Most recently, her legs have become extremely swollen, larger than any pregnant woman I have ever seen. The skin on her feet is breaking open and peeling. The doctors can't find the cause, but I think it is the topamax. Has anyone else had this swelling?