Inflammatory bowel disease guidance

This section provides guidance on the treatment of patients with ulcerative colitis and Crohn's disease. The aim of treatment is the induction and maintenance of sustained clinical and endoscopic steroid-free remission using the least toxic therapy. Treatment strategy is influenced by disease activity (mild/moderate/severe), distribution, pattern (e.g. relapse pattern or extraintestinal manifestations) and response and side effects of previous medication.

Inflammatory bowel disease (IBD) is diagnosed and managed in secondary care. However, a number of medications used are suitable for continuation in primary care, some under formal shared care arrangements, others simply as repeat prescriptions of standard maintenance therapy. Aminosalicylates and corticosteroids form the mainstay of routine therapy.

A toolkit has been developed in partnership between the Royal College of General Practitioners (RCGP) Clinical Innovation and Research Centre and Crohn's and Colitis UK, to aid GPs and other primary care professionals when managing patients with IBD. This can be accessed here.

Referral guidance

When to refer for suspected IBD

  • Bloody diarrhoea for more than 1 week, particularly if accompanied by tenesmus, urgency, nocturnal episodes, incontinence and negative stool cultures.
  • Diarrhoea or abdominal pain + 1 or more of the following:
    • Weight loss
    • Extraintestinal manifestations
    • Family history of IBD
    • Abnormal investigations: iron/B12 deficiency anaemia or elevated CRP

Recognition of severe colitis

Consider admission directly to Gastroenterology for patients with 6 or more bloody motions/day + 1 or more of the following:

  • Pulse greater than 90/min
  • Fever greater than 37.8°C
  • Hb less than 10.5g/dl
  • CRP greater than 45mg/l

Ulcerative Colitis in Primary Care

Induction of remission

Mild-moderate disease: proctitis

  • Initial treatment: mesalazine suppositories 500mg - 1g/day.
  • If symptoms persist after 3-4 weeks, add oral mesalazine at a dose of 2 - 4g/day (Pentasa®) or 2.4 - 4.8g/day (Octasa®).
  • If patient is not improving on combination aminosalicylate therapy then refer to individual patient management plan, or contact consultant.

Mild-moderate disease: left sided or extensive

  • Start treatment with mesalazine foam or retention enema plus oral mesalazine 2g/day (Pentasa®) or 2.4g/day (Octasa®).
  • In moderately active disease, oral mesalazine 4g/day (Pentasa®) or 4.8g/day (Octasa®) increases clinical response (but not remission) and reduces time to bleeding cessation.
  • A reducing course of oral prednisolone is appropriate if symptoms fail to settle ≤ 4 weeks or deteriorate on treatment.

Severe disease

  • Phone gastroenterology SpR or consultant

When treating an acute flare with rectal mesalazine, local specialists note:

  • It can take up to 14 days before a response to treatment is seen
  • Once symptom free, patients should continue treatment for a minimum of 14 days, then alternate days for 7-14 days, then stop
  • Some patients may continue treatment several times each week (e.g. alternate days) as maintenance to prevent breakthrough bleeding (unlicensed frequency)

Maintenance of remission

  • Approximately 70% of patients with ulcerative colitis will relapse at 12 months.
  • Oral mesalazine 2g/ day (Pentasa®) or 2.4g/day (Octasa®) is the first line treatment for maintaining remission. The European Crohn's and Colitis Organisation (ECCO) guidelines recommend that patients remain on a maintenance dose of oral mesalazine of at least 2g per day.
  • Patients on higher doses could trial stepping down high dose oral mesalazine after being stable for 6-8 weeks. De-escalation of doses should be considered on an individual basis. Certain patients may need to remain on higher doses to maintain remission (specialist input should be sought for guidance).
  • 1g suppositories on alternate days are an acceptable alternative for proctitis (unlicensed frequency).
  • It is recommended that mesalazine is continued long-term since this may reduce the risk of colon cancer.
  • Patients who are experiencing symptoms on their current regimen should be reviewed and treatment optimised.

Crohn's disease in primary care

Induction of remission


  • Mild disease: no treatment or budesonide 9mg daily.
  • Moderate disease: budesonide 9mg daily or reducing course of prednisolone.


  • No treatment or reducing course of prednisolone.
  • Sulfasalazine 4g - second line option for mild disease associated with arthropathy.

Upper GI

Maintenance of remission

  • Smoking cessation is an important factor in maintaining remission.
  • There is no role for mesalazine in medically induced remission.
  • Patients who relapse early, or who have steroid dependent or refractory disease will be treated with azathioprine or mercaptopurine.


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