It’s a familiar scenario for many—you get sick, go to the doctor to see what’s wrong, the doctor writes you a prescription and you soon feel better.

Your doctor knows your medical history and can make decisions about how best to treat you. But in some cases it’s not easy for doctors to write prescriptions for the medications they know their patients need. It gets complicated for many through a process with insurance companies called step therapy that can create a series of road blocks for patients who are fighting serious, chronic diseases.