I would say that the least problematic cause for constipation would be the zonisamide the of the seizure meds listed but it depends on the person. Does she drink a lot of water and get plenty of exercise? Does she take stool softeners and/or Metamucil or similar. I've taken seizure medicines for almost 60 years and have had this problem from the beginning. Occasionally, I take magnesium citrate, which is a liquid-type laxative, but I don't take it very often.
Sometimes they're just really isn't a lot you can do and just have to do the best you can. I'm sorry to hear about the aggressive behavior. Is that type of behavior all the time or only when she has seizures? Has your doctor been to a G.I. doctor to get their suggestions of what you might be able to do. One Emergency room Dr. suggested that I take a stool softener as well as a certain type of laxative, but I can't remember the name of it. What he suggested definitely helped, but I no longer take it any longer, and I can't remember the name of it.
Take care,
Jake