Hi, My dog when she was 2, ( a golden retriever/lab mix) was started on Program the one with flea control and heartwomer. She developed ITP. A autoimmune problem with her platlets. She had to be put on predisone because her platlets were so low. She had a bone marrow biopsy, an ultrasound and many blood tests. She is finally went into remission and has been very good for many years. So I know that it was not her but the medication. If it was her it would have stayed not gotten better when she was taken off of it. I know other dogs have actually died because of this drug. they went into the same autoimmune except it attacked the red blood cells instead and the dogs died. Just thought you should add this to your problem meds. thanks Bev B.