I have Rheumatoid Arthritis and have just started a 5 day course of prednisilone (60mg per day for 5 days). My blood sugar has jumped to 24.5, but my arthritis has improved immediately. I am on Lantus 28units perday, Sitagliptin 1 a day and Metformin 2 grammes per day in 2 doses.I am very concerned that these high blood sugars are doing serious damage. I have started taking an additional 20 units of Lantus, but the blood sugars are still very high- Help please- what shall I do??