Chronic Functional Abdominal Pain

Persistent functional abdominal pain is a really common problem. It affects children more than adults but does affect many adults. Tig studies have shown that from 10-30% of people have functional persistent abdominal pain.

The syndrome has the word functional because there is no underlying organic pathology, meaning there is no disease causing the pain. This is a malfunction of something in your body, causing you to feel this really significant abdominal pain.

This article with look at:

  • Diagnosis
  • The Four Types of Functional Abdominal Pain
  • Treatment Options

How do you know if you have Functional Abdominal Pain Syndrome?

The classic definition is if you have more three episodes of three hours of pain over a period of three months.

Functional abdominal is a complex problem. It involves not only the person but their relationship with the world. There is a, a word that’s used in pain medicine to describe this: bio-psycho-social.

Bio what’s going on in the biology of your body. Psycho is what’s going on in your mind and social is your interaction with the world. Functional abdominal pain is caused by all three of these spheres interacting.

If all you do is focus just on what’s happening in your gut, you miss the bigger picture and are unlikely to get better.

Due to this complex interaction with us and our world, the treatments are complex and multilayered as is the actual assessment and management of the problem.

At the moment there is no agreement between all the experts as to the ‘perfect’ treatment. Instead, you’ll find that there are a lot of options.

In medicine, whenever there are a lot of options, it means each one doesn’t always work, therefore you have to try several before you hit on the one that will work for a particular person. This is the norm for complex problems.

“For every complex problem there is an answer that is clear, simple, and wrong.”

H. L. Mencken

The Four Types of Functional Abdominal Pain

There are four types of functional abdominal pain:

Functional dyspepsia.
Dyspepsia has an old English word, which means [inaudible] sort of discomfort in the upper abdomen, just above your belly button.

This is usually is related to problems with your stomach. Because it comes from your stomach, the pain is not improved or made worse by bowel motions.

Irritable Bowel Syndrome
Irritable bowel syndrome is when your gut become sensitized, and this is the most common type. It becomes irritated and the gut wall becomes more sensitive to changes in pressure.

Normally what happens in your gut is you have a long tube. Food is moved along this tube by a ring that contracts the tube. This ring moves along, pushing the food through the gut. As the pushes food along, the gut in front of the ring relaxes. This is called peristalisis.

The wall inside the gut itself is full of pressure sensors to manage this process. When there is a dysfunction or a malfunction in the gut, the contraction ring starts to move. What should happen is the gut relaxes.

But if somewhere along the gut there’s another contraction, the food is being pushed into an area that’s being stretched. The pressure goes right up there. The little pressure sensors sound the alarm.

And what you feel is this awful, cramping pain in your gut. It’s not due to a disease, it’s caused by a digestive malfunction. The movement of the gut has become disordered and therefore you have these pockets of high pressure. That’s the first part of irritable bowel syndrome.

The part second is that the little nerve endings become more sensitive to pressure over time. And then going up to your brain, you get what’s called visceral hypersensitivity. This is where the nerves start to amplify messages.

These three things work together to make digestion a very uncomfortable process. People with IBS have episodes of intense pain with which are relieved by a bowel motion but then come back.

Abdominal Migraines
Abdominal migraines are a very strange phenomenon that only occurs mainly in childhood. What happens is you get this intense abdominal pain of unknown cause. It’s thought to have nothing to do with the gut but instead is caused by a sensitivity amplification of messages from the gut.

This is sensitization of the nerves supplying the gut. You get this intense pain, which is much more common in children. And it’s often associated with awful vomiting. The child looks terribly ill. Occasionally in children it’s associated with horrible headaches.

What tends to happen is that these abdominal pains go away, and are replaced by migraines. That’s why it’s called abdominal migraine

Abdominal Wall Pain
The last is abdominal wall pain, which turns out to be a really common problem. This can be the primary cause of the person’s pain or may in fact be secondary to other things going on.

What happens in the abdominal wall pain is trigger points get turned on in the muscles of the abdominal wall.

Your abdominal wall is full of strong muscles and you have these tiny areas in the muscle which go into a protective spasm. These can be incredibly sore and refer pain into different areas depending on where the triggers are.

This is called myofascial pain and it is due to trigger points. What happens is that sometimes people have an initial incident like appendicitis or a bowel problem. That gets treated, but they’re left with ongoing pain, which is quite significant and sometimes almost as bad as the original cause.

Often, you’ll find trigger points in the abdominal wall, which can be simply treated for fast pain relief.


Functional abdominal pain is the perfect example of mind body interaction. What we know is that we have a mind, and the mind is billions of tiny little nerves that talk to each other.

As they talk to each other, they use what are called neuro-transmitters as messengers. One of the big messengers in the brain is something called serotonin. Over the last 20 or 30 years, researchers have found a massive, massive network of nerves right throughout the gut.

This is now being called the brian in your gut. And it produces far more seratonin than the brain. So this idea of the mind and body being separate is quite innacurate.

Once you start seeing this connection, it’s clear how things that affect your brain, like family life, academic pressure, life events, work stress, and social pressures will cause different messages to be sent down to your gut.

These messages that come to your gut can cause the movement of your gut to become wound up. Most people remember going for an exam and feeling a stomach cramp. Stress itself sends messages down to the motility in your gut and which can cause malfunction. You may get areas of pockets of high pressure and then the nerves that relay message between your mind and your gut will become sensitised.

All of this can come together to cause these episodes of significant abdominal pain, for which there is no organic cause.


Treating Functional Abdominal Pain

Remember I said before, there is no one treatment that works for everyone. Instead, there are many approaches that are tried.

The most important thing is to first identify any red flags. If you look at abdominal pain, there’ll be a small proportion where there is something significant going on.

From a medical point of view, you would be looking for blood in your bowel motion, weight loss, and other signs that there is inflammation in the gut. This is how you eliminate problems like cancer or an infection.

All of these things can be ruled out by fairly simple tests: blood tests, bowel motion tears, urine tests, a colonoscopy, or some very simple imaging, maybe ultrasound, uh, something like that.

Once these have been ruled out (and it’s only a small proportion of people who have them,) then you need to look at functional abdominal pain as the cause.

Understanding the complex bio-psychosocial picture that’s actually turned on the pain is vital, because then you can make the right treatment choices.

Cognitive Behavioural Therapy
The treatment that’s been shown more than any other to make a difference is what’s called CBT, or cognitive behavioral therapy treatment.

First, you need to understand your previous responses to the stresses of life, your beliefs, and the things that drive you. Next, you work to change your responses.

You have to let go of unhelpful and limiting beliefs, and learn how to cope with the stresses of life, without them affecting your gut. As you start to do that, the gut will start to become happier.

The FODMAP Diet
There are other treatments that have made a difference for irritable bowel syndrome. There’s the FODMAP diet. FODMAP is an acronym for a diet which eliminates short chain sugars. These increase the amount of gas that’s produced during digestions, and cutting them out makes your gut less irritable.

The FODMAP diet will exclude a whole lot of things from your gut which are surprising until you understand that they all have these little short chain sugars.

Other helpful treatments are taking probiotics and increasing fiber in your diet. There has been one study showing that peppermint oil as a soother was useful.

Simple painkillers like paracetamol can help a bit, as well as protein pump inhibitors, and powerful antacids can sometimes help.

How You Cope with Stress

The biggest thing is understanding the relationship between how you respond to the stresses in your life, and how your mind and your gut affect each other.

The majority of of children get grow out of functional abdominal pain. But about one third it can become a major life problem, which requires a lot of treatment.

People with functional abdominal pain have a higher risk of this changing at some stage into an inflammatory bowel disease. These are diseases like Crohn’s or ulcerative colitis.

Therefore, the other important thing is that if you learn to live with your chronic abdominal pain and then it becomes more severe, you need to have that investigated.