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Functional Abdominal Pain

Most otherwise-healthy children who repeatedly complain of a sore stomach, have functional abdominal pain. The term “functional” refers to the fact that there is no organic cause, meaning no blockage, inflammation or infection causing the discomfort. Nevertheless, the pain is very real, and is due to extra sensitivity of the digestive organs, sometimes combined with changes in gastrointestinal movement patterns. 

Our intestine has a complicated system of nerves and muscles that helps move food forward and carry out digestion. In some children, the nerves become very sensitive, and pain is experienced even during normal intestinal functions. This digestive tract sensitivity can be triggered by a variety of things, such as a viral or bacterial infection, stress, or an episode of constipation. Other family members may have a history of similar problems. Because of the pain, children may stop their usual school and play activities, which may cause more stress and anxiety which in turn worsen the pain. 

Fortunately, despite the recurrent episodes of pain, normal growth and general good health continue.

Functional pain is very common. About 10 – 15% of school-aged children will report episodes of recurrent pain. Another 15% experience pain, but do not go to the doctor for it.


The functional abdominal pain syndromes can be divided into 4 main conditions according to the symptoms hallmark-


  1. Functional abdominal pain

  2. Irritable bowel syndrome (IBS)

  3. Functional dyspepsia

  4. Abdominal migraine


How is functional abdominal pain diagnosed? 

A detailed history of how the pain started, how it progressed, its location, and other associated factors can often suggest a diagnosis of functional pain. In functional pain, growth is good and the physical exam is normal.

Basic blood, urine and stool tests are often performed to screen for other conditions that can cause recurrent pain. X-rays, other imaging studies, extensive lab tests and endoscopy are only recommended for children whose history, exam or basic lab results don’t fit with the diagnosis of functional pain. Your doctor will also follow your child to see if any changes take place which would suggest a different problem. 


How is functional abdominal pain treated? 

Treatment of functional abdominal pain-

unless some abnormal findings, your doctor may suggest some of these ways to help your child.

  • Reassuring your child - Often we cannot make abdominal pain go away, and parents’ anxiety can only make the pain worse. Knowing that there is not a serious or life-threatening problem can be important in reducing pain. The brain can alter the pain experience for better or worse. Based on what we currently know about FAP, the aim of treatment is to help the child gain control over the symptoms and improve daily function. The brain not only affects how you sense pain, it is also able to block pain. For this reason, treatments like relaxation, imagery, hypnosis, and cognitive-behavioural therapy can provide relief. They teach how to send signals that help block pain. 

  • Diet Therapy - Fermentable sugars-the sugars in drinks and candy- are often poorly absorbed. They ferment in the intestine, causing gas and cramps. Your doctor may suggest that you try eliminating fructose and sorbitol for about a week. This means no gum, candy, juice, or sweet drinks other than milk and water. One week is usually long enough. Your doctor may also suggest a dietary review in order to try and eliminate those carbohydrates from your child's diet (Low FODMAP diet )

  • Keeping a normal routine - keeping a normal routine is very important. Children should attend school unless they have a fever or are vomiting. Long absences from school only increase anxiety about returning to school and can make the pain worse. Usually, you can arrange with the school for your child to start with short days and to lie down for a short time during more severe pain. Most schools would rather make some changes so that the child doesn’t have to miss so much school.

  • Psychotherapy and cognitive behavioural therapy- Talking with a therapist may reduce stress and improve FAP symptoms. Two types of talk therapy used to treat FAP are cognitive behavioural therapy and psychodynamic, or interpersonal, therapy. Cognitive behavioural therapy focuses on the child’s thoughts and actions. Psychodynamic therapy focuses on how emotions affect FAP symptoms. This type of therapy often involves relaxation and stress management techniques.

  • Medicines - Three main types of medicines may be used for treatment.

    • Anti-spasm medicines including Buscopan and Peppermint Oil

    • Acid reduction medicines such as Gaviscon, Mylanta and Omeprazole

    • Pain modulators- For example, Amitriptyline, a type of an antidepressant may be used This medication doesn’t only treat depression, it also acts as a pain reliever, at a dose lower than for depression, for treatment of FAP and many other painful conditions.

These drugs can help stimulate the brain to increase the signals that block pain messages from the abdomen to the brain. It may take several weeks before you notice a difference.

How do I know if my child really has an upset stomach, or is trying to avoid going to school?

Many school-age children never think about faking it; assume the sore stomach is real. However, children and parents often forget that some sore tummies come from too much excitement or from worries.

For school morning bellyaches, use the "Rule of Ones." Two or more symptoms, bellyache and fever, or bellyache and vomiting should be taken more seriously than if the bellyache is the only one symptom.

The "Rule of Ones" may be used for two other common symptoms; infant regurgitation and toddler's diarrhoea. In the absence of a second symptom, these two problems are likely to be functional, meaning they are expected behaviours for that age group and are not a cause for alarm.


Why do symptoms seem to be worse in the morning and at bedtime in children? These are stressful times for a child. There are a number of children who have bedtime anxiety which will cause symptoms of functional abdominal pain at night, and also in the morning children will be under a fair amount of stress and anxiety facing the day, especially during school days. 


Shall I send my child to school when he or she is in pain from FAP?

Children often wake up in the morning complaining of severe symptoms and then by early afternoon or late morning will be symptom-free. This is difficult to understand for the parents. As the child stays home from school, part of the stress and anxiety decreases and the symptoms dissipate. Unfortunately, they may get into a vicious cycle where they become more nervous about missing school and making school work up, which will then increase their stress and anxiety level, and may increase pain that evening, prior to bed, and again the following morning. Children need to go to school, under these circumstances. They need to break the cycle of stress and anxiety, which is made worse by missing school.







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