My son was taking calacort steroid for muscular dystrophy and the dr changed to presidone steroid, son developed diabetes wasn’t told of side affect

My son was taking calacort steroid for muscular dystrophy since 2007 and the doctor just recently changed to presidone steroid due to insurance not covering the calcort steroid drug but there was a co pay assistance that would have paid for that drug. My son has developed type 1 diabetes as a result of taking the new steroid drug. We were not made aware that was a side affect or that he could develop diabetes.