Is Methylprednisolone In A Prostate Cancer Patient Recommended?

My grandfather is 73 years old and suddenly stopped taking methylprednisolone about two weeks ago. His doctor prescribed it for a sprained tendon. He is a prostate cancer survivor. He has diabetes, high blood pressure, gout and decreased kidney function. Since discontinuing the medication on day 2, he has suffered from loss of appetite, a ten pound drop in weight, stomach cramps and restlessness. He also takes Clonidine, Enalapril, Nadalol, Amlodipine, Hydralazine, Tekturna (for high blood pressure); Baby Aspirin; Glimperide and Januvia (for diabetes); Colchicine (periodically) for gout; Furosemide, Lipitor and Ferrous Sulfate (for cholesterol, I think). His doctor advised him to discontinue the Baby Aspirin. His stools have been dark, almost black for about two months prior to taking the methylprednisolone.