"Prednisone, a corticosteroid, is similar to a natural hormone produced by your adrenal glands. It often is used to replace this chemical when your body does not make enough of it. It relieves inflammation (swelling, heat, redness, and pain) and is used to treat certain forms of arthritis; skin, blood, kidney, eye, thyroid, and intestinal disorders (e.g., colitis); severe allergies; and asthma. Prednisone also is used with other drugs to prevent rejection of transplanted organs and to treat certain types of cancer."
After looking at about 8 different sites, I didn't find anything that said that it was a 17aa steroid or caused serious damage to the liver. However, I did find this:
"Prolonged therapy with prednisone causes the adrenal glands to atrophy and stop producing cortisol. When prednisone is discontinued after a period of prolonged therapy, the dose of prednisone must be tapered (lowered gradually) to allow the adrenal glands time to recover. "
hope it helps