The trouble is, if your doctor says you need the shot every 3 months, the insurance company will only cover it once every 6 months, and when you get an exception written up by your doctor they'll still deny the request. When a generic comes out that isn't as effective, they'll force you to switch, again against your doctor's orders.

People focus on how expensive healthcare in this country is because of this broken system, but to me the crazier thing is how much your insurance company can dictate how your doctor treats you.