I am a disabled healthcare professional. It is generally said that 5 mg of prednisone is equivalent to what the body produces naturally. But what is true for a population is not necessarily true for an individual. In my experience, weight matters, ie, low weight individuals respond differently than the average 70 kg man. Also most studies were done on men, so less information available about women. And in my experience, in periods of high stress (illness, car accidents, etc), a small but significant portion of patients will require “stress dose steroids “ . This makes sense as taking prednisone, even 5 mg, gives your adrenals a holiday, causing some shrinkage (or atrophy).

Of note, I haven’t seen this phenomenon with 2,5 mg of prednisone.