Shaping better health
REMEDY : BNSSG referral pathways

Irritable Bowel Syndrome

Checked: 01-10-2017 by Rob.Adams Next Review: 01-10-2019


These guidelines have been written with the support of Dr Mike Cohen (local GPSI) and Dr Tom Creed and Dr Melanie Lockett (consultant gastroenterologists) to help General Practitioners make the diagnosis of IBS in patients under the age of 40 without alarm symptoms and to support management of confirmed IBS in primary care.

Patients with IBS and other functional bowel symptoms are common in primary care. Recent studies estimate that up to 45% of patients referred to secondary care gastroenterology clinics will be found to have functional gut disorders. Some GPs will refer patients for endoscopy or to a gastroenterologist to rule out other causes prior to making a diagnosis however this is not advised by latest NICE guidelines or local clinicians. Given the current pressures on endoscopy services and secondary care gastroenterology there is a need to reduce unnecessary investigations and referrals. GPs need to be supported in making a positive diagnosis without endoscopy while feeling confident that they have ruled out other significant pathology. They then need the resources in primary care to manage patients in a structured way including access to dieticians, psychological support and gastroenterology GPSIs where necessary. Currently these services are fragmented and GPs are unsure how or where to seek help – sometimes resorting to referrals to secondary care which are often unnecessary. 

Diagnosis and Investigation in Primary Care

The key to a diagnosis of functional bowel disease is a good history, examination and investigations done in primary care.

There is a good summary of diagnostic criteria in CKS:

There is no diagnostic test for IBS but some tests in primary care can help to rule out other pathology:

  • FBC – to rule out anaemia.

  • TFT – to rule out thyroid disorders which can cause GI symptoms.

  • CRP – to help rule out inflammatory conditions.

  • TTG antibodies – to rule out coeliac disease.

  • Faecal calprotectin test (FC)– This stool test is now widely available and can be requested on ICE across BNSSG. It can help to rule out inflammatory bowel disease. Caution should be used in interpreting this test however as many other conditions can cause a raised or equivocal level. Local clinicians advise that the test should only be done if a referral is being considered (see below).  If FC is only marginally raised and there are no other alarm symptoms or concerns then it may be better to repeat rather than immediately refer for colonoscopy.

Mike Cohen comments:

‘We are gaining more experience with FC. GP’s need to know it detects any sort of inflammation in the gut and slight or moderate rises in FC levels may not mean too much. Infections and drugs can push up FC as well. If it is only slightly raised then my suggestion would be to repeat it- off NSAIDs and if possible PPI for 4 weeks. My mantra would be to use FC only if referring patient and NOT to use it routinely.’

Tom Creed advises:

‘if the first test result is elevated but less than 200, repeat the test after 4 to 6 weeks and ensure the patient is not on NSAIDs at the time of testing’.

A diagnosis can be made at this point if symptoms are consistent with IBS and the above tests are negative. The following investigations are therefore not routinely advised:

USS, sigmoidoscopy, colonoscopy, barium enema, faecal occult blood, hydrogen breath test, faecal ova and parasite test.

Red Flags

It is important to check for alarm symptoms/red flags and refer appropriately. Clinical Knowledge Summaries have a list of Red Flags and other differential diagnoses to consider.

Please also see the local 2WW referral criteria and pathways


Management in Primary Care


  • Assess type and severity of symptoms

  • Assess dietary triggers

  • Assess fibre intake

  • Assess physical activity

  • Assess psychological status


  • Lifestyle advice for patients can be found on the website.

  • Fibre – reduce intake of insoluble fibre and increase intake of soluble fibre (ispaghula, oats)

  • Caffeine – reduce caffeine intake – limit to 3 cups of tea or coffee a day.

  • Physical activity – aim for moderate intensity physical exercise for 30 minutes at least 5 times a week.

  • Stress – try to reduce and manage stress and create relaxation time.

  • FODMAP diet – developed in Australia and claims to be effective for about 70% of patients with IBS who try it. It is not directly referred to by NICE but there is a useful summary on the King’s College website which suggests it should only be used under supervision of a dietician. Locally, FODMAP advice is available via referral to secondary care dieticians and is not currently available in the community service.

  • Probiotics – there is no strong evidence for the use of probiotics in managing IBS. However, they are not known to be harmful and some patients may find benefit. Local advice is that probiotics can be trialled for 4 weeks to assess response. These are currently no licensed products in the UK and the medicine management team advice is that they should not be prescribed on the NHS but can be bought over the counter. Mike Cohen comments:

    ‘Probiotics containing bifido bacterium may help in bloating and diarrhoea. It is a minefield- patient needs to know that what they are taking contains live organisms. Many health food shops sell ones that contain no live organisms.’


Diet and lifestyle are the mainstay treatments for IBS but medication can be used if symptoms still not controlled.

  • Anti-spasmodics (for abdominal spasms) – e.g mebeverine, alverine, peppermint oil, buscopan.

  • Laxatives (for constipation) – e.g ispaghula, macrogol, senna (short term only). Avoid lactulose.

  • Anti-motility (for diarrhoea) e.g loperamide

  • TCA* ( for abdominal pain) if 1st line treatments not effective – e.g amitriptyline 5-10mg nocte initially and titrate up to 30mg if necessary.

  • SSRI* – if TCA ineffective and particularly if anxiety or depression.

*TCA and SSRI do not have a licence for treatment of IBS but are considered safe to use if antispasmodics have failed.

Other drugs currently not recommended for routine use include:

  • Rifaximin – only licensed in the UK for hepatic encephalopathy and travellers’ diarrhoea and not IBS. The local medicine management team advise it should not be prescribed outside of this license. 

  • Linaclotide is sometimes suggested as a second line laxative treatment but is currently an amber drug and therefore currently can only be initiated by a specialist.

Referral Guidance


If there are red flags – refer via local 2WW referral pathway

Community Gastroenterology Clinic (PRIME) 

Consider e-referral to this service if patients are aged 40 or over or if there is diagnostic uncertainty or poor response to management in primary care. Please ensure that a faecal calprotectin is done prior to referral. Patients will be assessed by a GPSI and an endoscopy may be undertaken as part of this assessment if indicated.For more information on referring to Prime please see  their Referral Guidelines (PDF)

Gastroenterology Consultant Led Advice and Guidance

Consider a Gastroenterology advice and guidance referral if more specific secondary care advice is required. Requests for advice can be submitted via e-referral. Responses are normally received within 3 working days.

Direct Access Endoscopy (PRIME, EGTC) 

Endoscopy outside of the 2WW pathway should only be undertaken if there is a clear indication. Routine endoscopy requests to the acute trusts should be avoided if possible given the pressure on their services.

Secondary Care Referral 

Patients with IBS should be referred to secondary care clinics on advice of another service or if other referral routes are not appropriate or not acceptable to the patient. Referrals to secondary care will be triaged at the BNSSG Referral Service and may be redirected to the community service if felt to be appropriate. If a secondary care outpatient referral is specifically required then this needs to be stated in the referral letter.

When to refer to other health professionals?


for advice on food exclusion diets or if general advice on diet does not improve symptoms. Bristol Community Health have produced a Brief guide to IBS and will accept referral for patient requiring dietary advice (but not currently not FODMAP). For FODMAP dietary advice then referral should be to secondary care dieticians.

Psychological therapies (CBT, relaxation, hypnotherapy, psychotherapy are all suggested)

CBT is available on NHS via Bristol Wellbeing therapies