Using Kevzara to taper down from prednisone

How do you know when you are successfully tapering down from Prednisone while on Kevzara? What levels of pain and fatigue are to be expected while tapering?

I am an 83 year old male who suddenly developed PMR symptoms in January, 2025 and was formally diagnosed by a GP in May, 2025. I started on 40 mg of Prednisone a day, tapering down to 15 mg. On December 5, 2025, a board certified rheumatologist put me on Kevzara on December 5, 2025 with injections every two weeks for a total of 3 injections over 6 weeks.

I was told to taper down 1 mg every 7 days. I could not do it that fast but since December 5, I have tapered down to 13mg with few problems. However when I went down to 12.5 mg on January 13, 3 days ago, significant fatigue set in and the pain in my hips was sharp and made walking around the apartment in the morning difficult. By late afternoon the pain has worn off and I can walk about 8000 steps around 4pm but not until then.

Is this kind of fatigue and pain normal when tapering down just .5 mg of prednisone? How can you tell if it's PMR or adrenal insufficiency? How do you know the Kevzara is working?