Functional Abdominal Pain

Functional abdominal pain refers to stomach aches, usually around the belly button, that commonly occur in school-age children. Most otherwise healthy children who repeatedly complain of stomach aches for two months or longer have functional abdominal pain.

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

A child’s intestine has a complex system of nerves and muscles that helps move food through for digestion. In some children, the nerves become sensitive, causing pain even during normal functions.

Digestive tract sensitivity can be triggered by different things, such as infection, stress, or constipation. Other family members may have a history of similar problems. In many children, there is no clear explanation for why the pain started. The pain often interrupts a child’s usual school and play activities. However, despite the recurrent episodes of pain, normal growth and general good health continue in children with functional abdominal pain.

About 10%–15% of school-age children report episodes of recurrent pain. Another 15% experience pain but do not go to the doctor for it.

Most children with functional abdominal pain complain of pain around, above, or below the belly button. The pain usually lasts a few minutes and improves, although in some children it can last longer.

Sometimes, a child may also experience nausea (feeling like he or she might throw up) or have an urge to go to the bathroom and have a bowel movement. Triggers for such pain attacks can include eating and stressful situations, but often there is no identifiable cause.

If the pain recurs frequently, the child may ask to miss school.

In many cases, a careful history and physical by a pediatrician or pediatric gastroenterologist is all that is needed to make a diagnosis and to exclude more serious causes, such as Crohn’s disease, ulcerative colitis, or liver disease.

A detailed history of when the pain started, where it is in the body, and its relation to food or stress can often help diagnose functional pain. Children with functional pain have good growth, a normal physical examination, and no signs of serious disease, such as fever, weight loss, or blood in the stool.

Although a diagnosis of functional abdominal pain is made on the basis of history and examination, your child’s doctor may perform blood, urine, and stool tests. Tests are done to screen for other conditions that can cause recurrent pain.

In rare cases, your doctor may recommend additional testing, such as more lab tests, X-rays, ultrasound, and endoscopy (examining the inside of the stomach with an instrument called an endoscope). More commonly, your doctor may recommend a treatment plan and follow your child to see if the pain improves.

You, your doctor, and your child can partner to put you and your child, rather than the pain, back in charge of your child’s life. Identifying and managing your child’s pain triggers, such as constipation, stress, or lactose intolerance, often help reduce the pain.

Sometimes, medications to treat specific symptoms, such as acid-blocking medications for heartburn or laxatives for constipation, will help reduce the pain. In some children, dietary changes may be helpful, for example, reducing milk intake in a child with lactose intolerance.

However, the primary goal in treating functional abdominal pain is to treat the pain itself. In some children, non-narcotic pain medications such as cyproheptadine or amitriptyline may be helpful.

There are specific approaches to treat pain episodes, such as breathing or relaxation techniques, that your child can learn. An experienced child psychologist can also help treat pain symptoms. The psychologist may also identify and treat anxiety or depression, which are common in children with recurrent pain.

As a parent wanting to know if your child has pain, a good approach is to observe your child’s behavior rather than asking if he/she is in pain. It is important to prevent the pain from becoming a reason for missing school, changing your child’s social activities, or becoming the center of everyone’s attention at home.

Even if the pain continues, functional abdominal pain is not dangerous. It is important for your child to continue participating in activities and having a daily schedule. Being positive about getting better will send the right signals to your child.

Medications may be helpful for some children with functional abdominal pain. These and other specific approaches suitable for your child can be discussed with your doctor.

With appropriate follow-up and care by a pediatric gastroenterologist, more than 50% of children with abdominal pain improve and have less pain within a year.

Some children have ongoing pain despite treatment, and they may need more intensive treatment (medical, nutritional, or psychological) in a specialized center.

Some children with functional abdominal pain may develop irritable bowel syndrome (abdominal cramping associated with diarrhea or constipation) when they become adults. Patients with functional abdominal pain also may develop other pain symptoms such as headache or joint pains as they get older.

Author: S Patel, MD
Editor: Athos Bousvaros, MD
February 2021