Autism is a developmental disorder that makes socializing or communication difficult. More medical research is linking gastrointestinal problems to autism.

With communication struggles, it can be difficult to understand whether a child’s mood problems, sleep difficulties, and aggression are symptoms of autism, or if the symptoms are made worse due to physical discomfort from GI issues. Food rejection and aversion are often signs that the child struggles with stomach and digestive problems, but there may be more subtle symptoms.

Work with your pediatrician to get the right diagnosis, as your child may need medical treatment like antacids or laxatives to support their digestion. Working with a behavior therapist can also help to manage food aversion, rejection, and rituals.

You may decide to consult a nutritionist for help creating a healthy diet for your child. Many parents eliminate gluten and casein from meals, but it is important to replace these eliminations with healthy foods, especially fruits and vegetables. You may also give your child a dietary supplement, but it is important to ensure they learn healthy eating habits, which often requires assistance from a behavior therapist.

Autism & Gastrointestinal Problems: Understanding the Overlap

Autism is a developmental condition that clinicians typically diagnose based on behavior and learning changes in childhood. As the condition is studied more thoroughly, there are associated conditions that may be causally related.

Gastrointestinal problems, including stomach and digestive discomfort, are more common among people with autism compared to the general population. Gastrointestinal symptoms are between 9% and 70% more common in people on the autism spectrum compared to neurotypical people.

People with autism are more likely to experience gastrointestinal disorders like:

  • Celiac disease.
  • Colitis.
  • Crohn’s disease.
  • Esophagitis.
  • Gastroesophageal reflux disease.
  • Gastritis.
  • Inflammatory bowel disease.

A survey published in 2019 found that, out of 340 children with autism, 65% experienced constipation, 30% experienced diarrhea, and 23% experienced nausea. Symptoms of these conditions that are more likely to occur in people with autism include:

  • Abdominal pain.
  • Repeated belching.
  • Bloating.
  • Constipation or diarrhea.
  • Excessive flatulence.
  • Nausea and other stomach problems.
  • Reflux.
  • Vomiting.

Managing the symptoms of these conditions takes help from a doctor. In many cases, medication (either over-the-counter or prescription options) helps to treat discomfort and bloating.

Before gastrointestinal distress is diagnosed, struggling with this discomfort can cause irritability, aggressive behavior, trouble sleeping, hyperactivity and inattention, and feeding problems, including food rejection or aversion. Both internalizing and externalizing problem behaviors, even if the child undergoes appropriate behavior therapy, can be a sign that they are uncomfortable and need medical support.

Signs Your Child May Struggle With Gastrointestinal Problems

Understanding how gastrointestinal problems affect behaviors is important. For example, the 2019 survey reported that children on the autism spectrum who also struggled with nausea were 11% more likely to display aggressive behaviors. The study also found that younger children, between the ages of 2 and 5, were more likely to display aggressive behaviors from upper gastrointestinal issues. Older children, between the ages of 6 and 18, were more likely to have anxiety that disrupted their digestion and lower gastrointestinal discomfort like constipation or diarrhea.

Another survey of 960 children, published in 2015, assessed gastrointestinal disruption frequency along with severity of autism symptoms. Reporters found that abdominal pain, bloating and gaseousness, constipation, diarrhea, and pain during bowel movements were associated with worsened irritability, social withdrawal, stereotypy, and hyperactivity, compared to children with autism who did not struggle with these symptoms.

Communicating this discomfort is difficult —not just for young children, but also for children on the autism spectrum who may struggle to describe their discomfort or pain, who may be unable to form many sentences, or who may be completely nonverbal.

Signs that your child may be experiencing gastrointestinal problems but cannot express them include:

  • Coughing too much.
  • Tapping their chin or face.
  • Applying pressure to their abdomen.
  • Chewing on their clothes, fingers, or limbs.
  • Hitting their jaw or grinding their fist into it.
  • Sleep disturbances.
  • Eating too much to relieve discomfort.
  • Self-injurious behavioral changes in addition to outward aggression.

Treatment Combines Medicine & Behavior Therapy

Working with your pediatrician and behavior therapist can help your child get the diagnosis they need so they can begin treatment. One approach that many parents take is to adjust their children’s diets — often by removing gluten (wheat protein) and casein (dairy protein), which are common in the average child’s diet. Ideally, switching dietary approaches means you can encourage your child to eat a wider variety of healthy food, especially fruits and vegetables.

A systematic review in 2017 of 19 randomized trials involving a gluten-free, casein-free diet for children with autism found that there was no conclusive evidence to determine if this was a good approach or not. Some parents add dietary supplements to their child’s meals so they get enough nutrition, but it is more important to work with a behavior therapist to manage food aversion and rejection, so your child can eat a wider variety of healthy foods.

If your child also has an underlying gastrointestinal issue, getting treatment for that is important. This may include:

  • Laxatives as needed.
  • Fiber supplements.
  • Antidiarrheal medications.
  • Antibiotics.
  • Mild pain relievers like acetaminophen.
  • Antacids.
  • Rehydration solutions.
  • Corticosteroids.

If your child has a more serious underlying issue like Crohn’s disease or diverticulitis, there are prescription medications and even outpatient surgeries that may be needed. Working with your pediatrician means your child gets the diagnosis they need.

Elimination diets may help to discover food sensitivities. For children with struggles around eating and mealtimes, it’s important to work with a behavior therapist to manage these transitions.

Monitor Your Child’s Behaviors

More studies are needed to understand the gut-brain relationship and how this contributes to autism symptoms, inflammatory or digestive issues, and how the two play into each other. Trouble digesting food may increase symptoms of other conditions that are comorbid with autism, including allergies, immune system problems, sleep difficulty, and mood disorders. Clinicians should understand that children with autism are at greater risk for developing these digestive disorders, so screening for feeding problems, mood struggles, and sleep difficulty, along with other issues like constipation or diarrhea, can help the child get treatment as soon as possible.

Chronic gastrointestinal problems don’t just make autism symptoms worse; they can lead to long-term health issues. Managing healthy eating and behavioral symptoms together means your child can learn to take better care of themselves and communicate their needs as much as possible.

The leading treatment for autism is behavior therapy, so your child’s behavior therapist may notice changes in their symptoms that could indicate something else is making the child uncomfortable. Discussing specific new symptoms or changes in symptoms can mean that you understand which treatment approaches are working and which are not. You can then adjust your approach to gastrointestinal problems the same way you adjust to behavioral struggles — through observation and evidence.


Gastrointestinal Disorders and Autism. (2014). Comprehensive Guide to Autism.

Relationship Between Gastrointestinal Symptoms and Problem Behaviors in Autism Spectrum Disorder. (June 2019). Science Daily.

Gastrointestinal Problems in Children With Autism, Developmental Delays, or Typical Development. (May 2015). Journal of Autism and Developmental Disorders.

Common GI Disorders in Autism. Focus for Health.

Gastrointestinal Disorders. (March 2019).