What Causes Joint Pain And Fatigue Post Entocort Withdrawal?

My wife was diagnosed with lymphocytic colitis a few years back. She recently tapered off of Entocort because her doctor felt she had been on it too long. During the time she was tapering (from 9mg daily to 6 mg daily to 3 mg daily over a period of 2 months) she had joint pain, tiredness, and some itching. Is this common?