I have been up and down prednisone since 2011 and it is definitely not meant for long term use, and I always flare back up when I get down to low doses. I am still on it now and this time around I started on 60 mg and my doctor did a taper of down by 5 mg every 2 weeks until I got to 20 mg and now I am going down by 2.5 every 2 weeks and he plans to slow it even more when I get to 10 mg. Other doctors I have talked to have said that this taper is very slow, but I have also been told by many doctors that if a taper is too fast, it might not be effective. You could talk to your sons doctor about
doing a slower taper, but it is also a possibility that he is steroid dependent like me..Has the remicade been working for him? I really doubt 3 months is long enough to do significant damage like that, many people are left on it much longer than that.
I hope I could help!