Functional Abdominal Pain (FAP): Overview

What is functional abdominal pain (FAP)?

Most otherwise healthy children who repeatedly complain of stomachaches for a period of two months or more have functional abdominal pain. Functional abdominal pain is not a dangerous condition, unless it is a symptom of a more severe digestive problem. But if your child is complaining of persistent pain, it is important to talk to your doctor.

The term “functional” refers to the fact that there is no blockage, inflammation or infection causing the discomfort. Nevertheless, the pain is very real, and is due to the extra sensitivity of the digestive organs, sometimes combined with changes in gastrointestinal movement patterns and toileting behavior.

Your child’s intestine has a complicated system of nerves and muscles that moves food through the digestive tract. In some children, the nerves become very sensitive and pain is experienced even during normal intestinal functions. The pain can cause your child to cry, make his/her face pale or red and cause him/her to break into a sweat. 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 often stop their usual school and play activities. Fortunately, despite the recurrent episodes of pain, normal growth and general good health continue.

What causes functional abdominal pain?

The exact cause of functional abdominal pain is not known, and may vary from person to person. In some children, the nerves of the gastrointestinal tract become very sensitive and pain is experienced even when the intestines function normally. This digestive tract sensitivity can be triggered by a variety of things, such as a viral or bacterial infection, an episode of constipation or stress.

Typical stresses are school problems and family discord. Children who experience functional abdominal pain are often described as bright, sensitive and very demanding of themselves. This explains why school may be a source of stress even though the child is doing well academically and socially.

Other family members may have a history of similar problems.

Who gets functional abdominal pain?

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

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