@mp71

The physiological dose of prednisone ranges from 3 to 7 mg daily. It is probably closer to 5 mg which is the amount of prednisone that "adequately replaces" the amount of cortisol the body needs every day. It depends on the day and the amount of stress you experience which is why cortisol is called the "stress hormone."

I think 7 mg is not quite enough Prednisone to handle something stressful so that is when we start to have symptoms of a low cortisol level. I also think it explains why so many of us have a flare when we reach 7 mg of Prednisone when something stressful happens.

An endocrinologist told me I had to remain on a Prednisone dose of 3 mg or less for an extended period of time in order for my adrenals to start to function again.

Some sources say 3 mg of Prednisone is the"physiological" dose, meaning it mimics the amount of cortisol the adrenal make during "low stress" days. The adrenals are capable of producing much more cortisol when stress is high. In any case you need to be less than the physiological dose for the adrenals to begin to wake up.

The adrenals don't wake up very quickly so it takes a long time to taper off Prednisone. When my cortisol level was low, I was told not to taper my Prednisone dose any lower than 3 mg for as long as it took for my cortisol level to improve. Meanwhile, I was told not to increase my Prednisone dose unless I absolutely needed to. It was difficult to stay on 3 mg when someone else said to increase my prednisone dose for "niggles of pain."