You can help limit the water retention and weight gain by limiting your salt intake. In addition to making you hungry, steroids make you crave salt. Also, of course, watch the calories. Stock up on celery, carrots and other healthy snacks so when the steroids start craving you can stuff your mouth with those.
Make sure you have ample potassium in your diet; in addition to hoarding sodium, steroids will deplete your body of potassium and can cause severe muscle cramps, often lower leg cramps in the middle of the night. I always started the day with a glass of orange juice and ended it with a banana.
It's also a good idea to take large doses of calcium with D3 to combat the potential bone loss. You should be taking at least 1000 mg of calcium with vitamin D3 daily. Also try to do some weight-bearing or resistance activities every day.
For those of us with chronic diseases that may require steroids, two months is considered just the lowest level of "long-term" use. Usually the more severe long-term side effects don't appear until much longer use. However, it will be important to monitor your blood sugar as steroids will increase it, sometimes dramatically. As an example, my own blood glucose level will go up by as much as 50 points when on steroids. Follow up on this with your primary care physician; some people require anti-diabetic drugs short-term.
I know nothing about your primary condition, hopefully another member will chime in on that soon.
Thyroid forum moderator
Ulcerative colitis since 2001 in 7th year of remission with Remicade.
Inflammatory osteoarthritis; osteonecrosis from steroids
Grave's disease treated with radioactive iodine and now on Levothyroxine.
Type II diabetes induced by steroids.
Eczema, darn it!