Answer: Depends on how long the treatment is given for. Short-term (<7 days) or Long-term (>7 days), this usually is more than a couple months.
Explanation:
Abrupt suspension of a corticosteroid in a short-term course treatment is safe. But when a corticosteroid is given long term, the exogenous source of corticosteroid causes adrenal atrophy, and when the medication is abruptly suspended the adrenal glands won't be able to produce cortisol (that's why it should be gradually tapered off).
In this case, there is no reason to gradually suspend the medication, as the course of treatment should be short-term.