You have started on a lower dose than most of us. That might be because your Doctor is unsure about your diagnosis or your blood results indicate a lower level of inflammation. PMR can be difficult to diagnose because the symptoms are similar to other arthritis and rheumatoid conditions. In classic PMR cases, the patient is crippled with pain and stiffness due to extreme unrelenting inflammation and within a few days of taking 20mg Prednisone is completely pain free and functioning normally again (this is only temporary). This is a diagnostic sign that the patient has PMR and not some other condition.