Hi cjd - it is not in the current NICE guidelines although I am sure they are
open to review
These are the UK guidelines
"Inducing remission: step 1 therapy for mild to moderate ulcerative colitis
To induce remission in people with a mild to moderate first presentation or inflammatory exacerbation of proctitis or proctosigmoiditis:
offer a topical aminosalicylate
alone (suppository or enema, taking into account the person's preferences) or
consider adding an oral aminosalicylate to a topical aminosalicylate or
consider an oral aminosalicylate alone, taking into account the person's preferences and explaining that this is not as effective as a topical aminosalicylate alone or combined treatment.
"
From here publications.nice.org.uk/ulcerative-colitis-cg166/introduction
I am sure though that an experienced GI who has seen pred enemas work for proctitis would still want to prescribe them if the mesalazine was not working.