Hey there,
I hope your side effects simmer down quickly! In doing a little research about prednisone, I find that it can inflame the gut. My daughter has some food sensitivities that inflame her gut, and when they flare up one of her symptoms is bumpy, dry skin that resembles (or perhaps it is?) KP. Adding a probiotic supplement to her diet seemed to help her skin when she had flare ups.

Maybe attacking the KP from inside (probiotics) and out (lotions and AHAs) will help?

Best,
Susan