Chronic inflammation, pain, dysautonomia. medrol (methylprednisolone) for a week helps immensely but can't stay on it, obviously. would florinef have same effect?

No, distinct steroid: Medrol is methylprednisolone and Florinef is fludrocortisone. While both are corticosteroids and have overlapping effects, they are not identical. Florinef would be more likely to increase blood pressure, possibly to dangerous levels. With close monitoring, oral prednisone is sometimes used chronically: alas, all prescription steroids have concerning side effects when used chronically.