IBS (Irritable Bowel Syndrome) Diagnosis

Medically reviewed by:

Dr Sarah Marshall - Medical Officer

Updated: Aug 18, 2021

Next review: Aug 18, 2022

There isn’t one test to diagnose IBS, instead, the doctor will listen to the symptoms you have, ask about the length of time you have had them and enquire about your diet, lifestyle and other factors that may contribute towards it.

They will also want to know about the type of pain you experience, where and when you have it and if you’ve noticed whether anything triggers it, such as certain foods or situations.

IBS is a ‘diagnosis of exclusion’. This means a few basic tests are usually needed to rule out other conditions that can sometimes mimic IBS.

The doctor can refer you for these further investigations or to see a specialist. This is especially important if you have blood or mucus in your stools (poo), have lost a lot of weight for no apparent reason, or if they believe you are anaemic. These symptoms are not common in people with IBS

If you have had the following symptoms for six months or more, then it is an indication that you may have IBS:

A change in your bowel habits, including constipation or diarrhoea
Bloating
Wind
Tummy discomfort or pain that eases after going to the toilet
Symptoms that worsen after you eat (this may only be after eating certain foods)

Speak to a doctor about your symptoms if this is the case.

Tests for most people with suspected IBS should include:

A full blood count test (FBC) to rule out anaemia, which can be associated with many different bowel disorders.
Erythrocyte sedimentation rate (ESR) or C- Reactive Protein (CRP), which can show if you have any inflammation in your body, suggesting that IBS is not the problem.
A test for coeliac disease, which is when you are allergic to gluten.
A stool test to check whether you have a protein in your body called faecal calprotectin, which can be a sign of inflammatory bowel disease (IBD).
In rarer cases, a gastroscopy or colonoscopy may be carried out.

IBS (Irritable Bowel Syndrome) Diagnosis

Dr Sarah Marshall - Medical Officer

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