When you wrote you had a TAB, my mind went immediately to therapeutic abortion. And I realized what a silly mistake; of course you meant temporal artery biopsy. Just to remind you that GCA is not always focused in the head.
Dr.Das Gupta's ( a world expert in GCA and PMR) scholarly article of 2017, makes it clear that GCA can be in the chest, groin, neck, abdomen and anywhere in the body where large vessels are predominant. So do keep that in mind.
I imagine from your comment that you were having headaches; just keep in mind it is not always the head where GCA does it's damage. I am do hope you are fine, but I don't know how one would taper from a large dose of Prednisone you were on a short time. Tension headaches are quite different I understand than GCA headaches.
I would follow your doctor's advice. He put you on the meds; he should be the one to advise you.
