What is the initial treatment for colitis ulcerativa (ulcerative colitis)?

Initial Treatment for Ulcerative Colitis

The initial treatment for ulcerative colitis should be a combination of topical mesalazine 1 g/day with oral mesalazine ≥ 2.4 g/day, which is more effective than either treatment alone for controlling inflammation and symptoms. 1, 2

Treatment Based on Disease Extent

Proctitis (Distal Disease)

• A mesalazine 1-g suppository once daily is the preferred initial treatment for mild or moderately active proctitis 2
• Mesalazine foam or enemas are an alternative, but suppositories deliver the drug more effectively to the rectum and are better tolerated 2
• Topical mesalazine is more effective than topical corticosteroids and should be preferred 2, 1
• Combining topical mesalazine with oral mesalazine or topical steroids is more effective than either alone 2, 3

Left-Sided Colitis

• Mild to moderately active left-sided ulcerative colitis should initially be treated with an aminosalicylate enema ≥ 1 g/day combined with oral mesalazine ≥ 2.4 g/day 2
• This combination is more effective than oral or topical aminosalicylates, or topical steroids alone 2, 1
• Once-daily dosing with mesalazine is as effective as divided doses and may improve adherence 2, 3

Extensive Colitis

• Mild to moderately active extensive ulcerative colitis should initially be treated with an aminosalicylate enema 1 g/day combined with oral mesalazine ≥ 2.4 g/day 2
• Higher dose of oral mesalazine (4.8 g/day) may be more beneficial for patients with moderate disease 2, 4

Treatment Escalation Algorithm

1. First-line therapy: Combination of topical mesalazine (≥ 1 g/day) plus oral mesalazine (≥ 2.4 g/day) 1, 2

2. If no improvement within 10-14 days or symptoms worsen:

   • Consider increasing oral mesalazine dose to 4.8 g/day 2, 5
   • Continue treatment for up to 40 days before determining failure, as sustained complete remission may take time 2

3. If inadequate response to optimized mesalazine therapy:

   • Add oral corticosteroids such as prednisolone 40 mg daily with tapering over 6-8 weeks 2, 1
   • Alternatively, consider budesonide MMX 9 mg/day for left-sided disease as it has fewer systemic side effects than conventional steroids 2

4. For refractory disease:

   • Systemic steroids, immunosuppressants, and/or biologics may be required 2
   • Severe extensive colitis requires hospital admission for intensive treatment 2, 3

Important Considerations

• Oral budesonide MMX 9 mg/day can be used as an alternative to conventional steroids in patients with mild to moderate UC who have inadequate response to 5-ASA 2
• The median time to cessation of rectal bleeding is approximately 9 days with high-dose mesalazine (4.8 g/day) compared to 16 days with standard dose (2.4 g/day) 2
• Patients who do not respond to 8 weeks of oral 5-ASA may enter clinical remission after a further 8 weeks of high-dose (4.8 g) therapy 2
• Long-term steroid use should be avoided due to significant side effects 2, 6
• Regular monitoring of renal function is recommended for patients on long-term 5-ASA therapy, including eGFR before starting, after 2–3 months, and then annually 2

Maintenance Therapy

• After achieving remission, maintenance therapy with mesalazine should be continued to prevent relapse 1, 7
• Lifelong maintenance therapy is generally recommended, especially for those with left-sided or extensive disease 1, 3

By following this treatment algorithm, patients with ulcerative colitis can achieve optimal outcomes in terms of symptom control, mucosal healing, and improved quality of life.