A prescription comes from a doctor, end of story. When you get a prescription you can always pay for it yourself without insurance. No one says you have to involve insurance. It's the doctor who will say whether or not you're low and whether or not they will treat you, and if you are actually low but they won't give you anything, go to another doctor. Do your due diligence if you think it's a real medical issue. Other than that, your post is bordering on asking for a source so just a warning.