My Mother, 79 Years Old, Has Been Using Voltaren Gel

My mother, 79 years old, has been using Voltaren Gel 2mg q12h for the past week for low back pain. She has called me and indicated that she feels quivery on the inside. She is on several different medications for cholesterol, HBP, depression. Would any of these medications be contraindicated with the Voltaren Gel?