Have you considered talking to a therapist about this? Or even your GP? Are you a diabetic or using the med for something else? If you are diabetic, then how are you managing the diabetes? Anorexia is a slow way of suicide if you let it take complete control. Are you able to drink anything? Maybe try smoothies or products like Ensure/Boost to get your nutrients. Why do you think it is anxiety related? For me, the only anxiety I had was when I was lying to my parents about whether I ate or not. When you starve yourself for a certain amount of time, you lose your hunger signals, thus resulting in having little to no appetite. It takes about a year for these signals to return once you have restored your weight to a healthy weight. And even then those signals get confused, at least they did with me.

I hope you are able to get the help you need.