Medrol and methylprednisolone(which is a weaker steriod) make lots of people mean as a snake. I am a pharmacy technician, and when we council patients we always remind them that of the possible side effects. The most common ones are weight gain,anger,aggression, reduced immune response, and if taken long enough skin thinning. I had pretty much the same issue the last time I took prednisone 20mg for an old back injury that flares up periodically. I'm glad you are feeling better though.