Hello emily,
She may be having a reaction to her medication. You ned to bring her to the doctor to get a physical exam and see if they can diagnose her. I would say to get her off her medication but I don't know what she is taking. If she decides to get off her medication, she needs to tell her doctor about that. Her doctor will tell her what to do. He/she may need to give her a different kind of medication in place of what she is taking. Nevertheless, it sounds like she needs medical attention. Being over weight doesn't help the situation any. Ideally, she needs to go on a diet to get her weight down as soon as possible. Being over weight opens up all kinds of medical issues. To avoid other complications, get her to lose some weight.