Hi, My 87 year old mother in-law is taking Pradaxa, Diltazem, thyroid med, and Lasix dail. She has been having sporadic back pain. She is really a type of binge eater in that she doesn t vary her diet a month or two. She is currently only wanting canned spinach, grapefruit and cottage cheese which sounds like a pretty healthy diet for most of us, but I was wondering if the grapefruit could be causing the muscle spasm/back pain? She is supposed to take potassium tablets daily, but is pretty stubborn and doesn t like them, so only 2-3 times a week do we get her to choke them down.