Problem: A woman has severe IBS and takes hyoscyamine sulfate (Levsin), simethicone (Phazyme), and a TCA. She reports having continued severe diarrhea. The primary care NP should: Need Assignment Help? O order diphenoxylate (Lomotil). O prescribe alosetron after ruling out pregnancy. increase the fiber in her diet to 30 g per day. O refer her to a gastroenterologist for endoscopy.