I am on Prednisone, I take 2.5 Mg in the morning and 5 Mg in the evening.  As long as your doses are small you should not have any problems.  I have been on it since I was 16.  If you go to 15 or 20Mg of it then it might not be a great idea, if you are worried about weight gain.  They use that on patients in hospitals to help them get an appetite, 20 Mg helps you to get an appetite.  I see nothing wrong with it, and it has never caused me any other side effects.