Is it ok to take 800 mg of advil (ibuprofen) (600 plain advil (ibuprofen) and 1 200 advil (ibuprofen) pm) nightly? it's about the only thing works for my insomnia!

Be careful: Usually it is the diphenhydramine in the Advil PM that helps sleep. Unless you also have pain that is keeping you up, you don‘t need the ibuprofen/advil part of it. You could develop tolerance where the diphenhydramine can quit working if you take daily. It is also considered a potentially unsafe medication because of your age. Talk to your doctor.