How is IBS diagnosed?

If you’re currently struggling with gut issues such as abdominal pain, bloating, gas, constipation or diarrhea, chances are that you may have come across IBS, also known as Irritable Bowel Syndrome as a possible diagnosis.

You may have also received a diagnosis of IBS already.

But either way, if you have severe IBS symptoms, it’s not uncommon to worry that there is something more serious happening because of the level of pain and discomfort you’re in.

In this case, either you, your doctor, or both of you will want to have additional tests carried out to check what’s happening in your gut. So what are these tests? And how are they used to diagnosis IBS?

In this post and video I’m going to take you through 5 of the most common tests that your doctor might recommend to help diagnose your gut issues.

Getting a diagnosis of IBS (Irritable Bowel Syndrome) can be a long and frustrating journey. So my hope is that I can help you understand not only the most common tests used, but how they are used, and how they can help to diagnose IBS.

How is IBS diagnosed?

Now when it comes to IBS, unfortunately, there is no set test, so instead IBS is diagnosed based on your symptoms.

The criteria for a positive IBS diagnosis is summarised as experiencing abdominal pain which is related to going to the toilet, and a change in frequency and consistency of stools for at least a 3 month period.

This criteria is part of something called the Rome Criteria and at this point in time, we are up to Version IV.

But a diagnosis of IBS can also be made based on your symptoms, and by excluding a number of other conditions using diagnostic tests based on your symptoms and personal background.

Now in most cases, a diagnosis of IBS can be made without additional tests, but if your symptoms include anemia, bleeding from your bottom or blood in your stool, a fever, significant weight loss, or the sudden onset of symptoms after the age of 40, then testing would usually be indicated.

So let’s go through the 5 tests which your doctor might request and why.

1. Blood Test

A fairly likely scenario is that your doctor will start with a blood test to check for low iron levels and also inflammatory markers in the body. Now a blood test is fairly low invasive and can help reveal a number of things.

For example, low iron can point to anemia and can also point to internal bleeding which can occur with Inflammatory Bowel Disease, also known as IBD. Raised inflammatory markers in your blood may also signal that your symptoms may be due to an inflammatory disease.

For more on the differences between IBS and IBD, make sure you check out this post here.

2. Stool Analysis

A stool analysis can check for both blood in your stool (another sign of Inflammatory Bowel Disease) and it can also check for signs of infection and parasites.

Your doctor will be looking for different things depending on your own personal symptoms and background, but a stool analysis can help to rule out other gut disorders. It’s also a very low invasive way to get a clearer look at what is going on.

3. A Sigmoidoscopy

A Sigmoidoscopy is a thin flexible instrument that is inserted up into your rectum and is used to take a closer look at the final part of your large intestine, which is called your sigmoid colon.

This is the final 40 centimeters or so before it reaches your rectum, and is the final part of your digestive system and connects your large intestine to your anus.

So why would you be referred for this test?

Well a Sigmoidoscopy is used by your doctor or specialist to rule out a structural or infectious disease and is also less invasive than a colonoscopy which I’ll cover shortly.

4. A barium enema

If you are over the age of 40 or have a family history of colon cancer or polyps, your doctor may recommend this test.

Now I get that it sounds a bit ominous, so let me explain what it is and why it’s used.

A barium enema is a test that helps to highlight your large bowel (which includes your colon and rectum) so that it can be clearly seen on an X-ray. This is because unlike X-rays for other parts of your body, some preliminary preparation is needed to make your digestive tract visible.

During this test, a white liquid called barium is passed into your bowel through your bottom, and this test is usually carried out at a hospital radiology department by a radiologist or radiographer.

Nowadays, barium enemas aren’t carried out very often, as alternative tests such as a colonoscopy are preferred.

But a barium enema can sometimes be a useful way of finding the cause of problems like blood in your stools or a constant change in your bowel habits.

5. A colonoscopy

A colonoscopy is a test to check the inside of your bowels.

As it’s a pretty invasive test it would generally only be recommended if your symptoms were seen as red flags by your doctor, or your personal history warranted further investigation.

As I mentioned at the start of this post, these tests are not generally required for the diagnosis of IBS, but if your doctor does refer you for a colonoscopy, then they are wanting to get more information on what’s going on inside.

So what is this test?

During a colonoscopy a  long, thin, flexible tube with a small camera inside it is passed into your bottom and up into your bowel. 

Now despite its invasive nature, a colonoscopy is very helpful, because it can look for a number of things:

  1. Firstly, it can help to identify the cause of your bowel symptoms. For example, if you are experiencing bleeding from your bottom/finding blood in your stool, suffering with ongoing diarrhea or constipation that does not go away. Or if you are losing weight or feeling really tired for no reason.
  2. Secondly, a colonoscopy can be used to check for growths inside of your bowel such as polyps or if there is a suspicion of cancer, and;
  3. Thirdly, a colonoscopy can be used to look for signs of other bowel conditions such as Crohn’s disease, diverticular disease or diverticulitis, ulcerative colitis, and bowel cancer.

In summary

Now with all the tests, what your doctor recommends for you is going to be 100% based on your personal situation, so the information I can give to is general in nature and should definitely not be used to diagnose what’s happening in your gut.

But if you’re tired of struggling with your IBS symptoms alone and you don’t know where to turn next, then you’re in the right place.

I work with clients all around the world inside of my gut directed hypnotherapy programs. With almost 40 years of solid evidence behind it, gut directed hypnotherapy has been shown to reduce IBS symptoms in more than 70-80% of people.

If you’d like to explore whether my program will be the right fit for you, then book your free 30-minute discovery call here, and let’s talk.

How is IBS Diagnosed 5 Tests Your Doctor May Recommend

JAYNE CORNER - COPYRIGHT 2022 ©

The Calm & Happy Gut

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