Forty mg has been shown to be the optimal daily dosage of prednisone for outpatients requiring oral steroids for active proctocolitis. Although daily doses of oral steroids are commonly divided, a single dose each morning causes less adrenal suppression and is more convenient to take. A randomized controlled trial has been performed on patients with proctocolitis, in which 23 received 40 mg prednisolone each morning as one dose, and 22 received 10 mg four times a day, over two weeks. Physicians unaware of the dosage schedule scored the disease activity and assessed the steroid side-effects when the patient entered the trial, at day 7 and at day 14. Of those taking the divided dose the disease improved in 17 and failed to improve in five. No side-effects were observed in ten patients. Of those receiving a once daily regimen, 17 improved and six did not. Nine patients had no side-effects. Further assessment showed no difference between the two groups either in response rate or side-effects produced. When oral steroids are indicated for active proctocolitis, 40 mg prednisolone, as a single dose each morning can be recommended.