IBS isn’t just one condition. It’s split into several subtypes, depending on the prevalence of specific symptoms. IBS-C refers to the constipation-predominant type. It’s characterised by hard stools, straining, infrequent bowel movements, and a feeling of incomplete emptying.

But how do you distinguish IBS-C from chronic constipation?

Recurring abdominal pain associated with changes in bowel habit is what points more strongly towards IBS-C rather than functional constipation.

If you already have IBS-C and your current treatment has not provided enough relief, you can learn more about our current IBS-C research study.

What Is IBS-C?

IBS-C refers to irritable bowel syndrome with constipation predominance. It means constipation is the predominant bowel symptom alongside recurrent abdominal pain.

The confusion often comes when symptoms fluctuate or someone with IBS-C occasionally experiences diarrhoea. Other changes in bowel habit can occur, but constipation is predominant.

If diarrhoea predominates, a person may have IBS-D. If both constipation and diarrhoea are prominent, they may have IBS-M (mixed).

IBS-C Symptoms vs Functional Constipation

IBS-C and functional constipation can be difficult to tell apart. The primary difference is the recurring abdominal pain.

Here’s a quick overview of the two conditions:

The diagnostic criteria for functional constipation mainly focuses on difficult or infrequent stool passage and specifically require that IBS criteria are not met. This is important as the treatments for the two conditions can be slightly different.

How Do Doctors Tell IBS-C and Chronic Constipation Apart?

There is no single test that confirms IBS-C or functional constipation. Doctors assess the pattern of symptoms and may use tests to check for other causes.

A GP will look at:

• whether abdominal pain is present

• whether pain changes after opening the bowels

• stool frequency and consistency

• how long symptoms have persisted

• bloating and incomplete emptying

• whether anything suggests another condition

The main diagnostic criteria are known as Rome IV[GU1]. For IBS, recurrent abdominal pain must be associated with at least two of the following: bowel movements, a change in stool frequency, or a change in stool form. Functional constipation, by contrast, is defined mainly by symptoms such as hard stools, straining, incomplete evacuation, or fewer than three spontaneous bowel movements per week without meeting IBS criteria.

Why Does Getting the Right Diagnosis Matter?

You might wonder why it matters. The distinction can determine treatment and eligibility for clinical research. IBS-C involves pain and other gut symptoms that may need attention alongside the constipation.

For example, low-dose amitriptyline may be considered for persistent IBS pain, but it can worsen constipation, so a clinician needs to weigh its benefits and risks.

Could My Symptoms Be Something Other Than IBS-C?

Neither IBS-C nor functional constipation should be self-diagnosed. A clinician can assess your symptoms and consider whether another condition needs investigating.

The NHS currently advises seeing a GP if suspected IBS symptoms have persisted for more than four weeks. Because symptoms can overlap with other conditions, your doctor may recommend blood tests, including a test for coeliac disease. Other tests depend on your symptoms and any warning signs.

Follow the link to read more about constipation symptoms and their potential complications.

What If My IBS-C Treatment Is Not Working?

IBS can be a difficult condition to treat because there is no single treatment that works for everyone. Instead, medications aim to minimise individual symptoms. For example, if constipation is the main problem, laxatives may be prescribed to soften stools and make them easier to pass. lifestyle changes

If your IBS-C treatment isn’t working, it doesn’t necessarily mean the diagnosis is wrong. However, it may be worth speaking to your GP about whether other treatment options or further investigation are appropriate.

Research is also ongoing into new approaches to IBS-C. Adults whose current treatment has not provided enough relief may wish to learn more about the IBS-C research study currently being conducted and decide whether taking part is something they would like to explore.

Ultimately, the key difference between IBS-C and chronic constipation is the wider symptom pattern, particularly recurrent abdominal pain and discomfort linked to bowel habit. If you are unsure which condition best fits your symptoms, speak to your GP for advice and appropriate assessment.

Read the following article: Thinking About Joining an IBS Clinical Trial? What to Expect and Questions to Ask