There is no reason why a person can't do a "fast taper" if you have been on 40 mg for only 5 days. I did this countless times for flares of another autoimmune disorder. I started with anywhere from 60 to 100 mg and took that for 5 days until I got the response I wanted. Then I would taper by 5 or 10 mg every day depending on how I felt. When everything went well, I was off Prednisone again in less than a month.

With all the hype that Prednisone can only be tapered slowly, people expect to be on prednisone for years when PMR is diagnosed. That is too much time and the adrenals do shut and it becomes harder and harder to taper off Prednisone.

Eventually treatment for PMR will evolve and Prednisone will only be used as a "bridge" to something equally as effective. A medication that doesn't suppress adrenal function is needed. For me, that medication was Actemra (tocilizumab) but it still necessitated a slow Prednisone taper of a year for my adrenal function to recover.

I shouldn't say "slow taper" because I quickly tapered to 3 mg after Actemra was started. Then I had to stay on a 3 mg "maintenance dose" of Prednisone for many months to offset my low cortisol level. This allowed my adrenals some room to operate.

To add insult to injury, my endocrinologist said I could simply stop Prednisone after my cortisol level improved. According to my endocrinologist, a 3 mg dose of prednisone was such a small dose there was no need to taper when my cortisol level was adequate. I could simply go to zero without tapering.

Don't attempt any of this at home ... medical supervision is required.

A "Prednisone bridge" to more effective treatment is how many autoimmune disorders are currently being treated. PMR has been slow to evolve since more effective treatment has never been found. Probably because nobody ever did the research and looked for an alternative treatment for PMR.