Gastrocolic reflex is one of your body’s natural reflexes. It signals your colon to empty food once it gets to your stomach to make room for more. But, if the reflex goes into overdrive, you may have symptoms that require treatment.

When your gastrocolic reflex goes into overdrive, it may feel as if “food is going right through you.” You might head straight to the washroom after eating, or feel a number of symptoms such as pain, cramping, diarrhea, or constipation.

This exaggerated gastrocolic reflex isn’t a condition in itself. It’s typically a symptom of irritable bowel syndrome (IBS) in adults. In infants, it’s completely normal. Keep reading to learn more about your gastrocolic reflex, how it’s affected by IBS, and how you may be able to control it.

Irritable bowel syndrome (IBS)

People with an overactive gastrocolic reflex may have IBS. IBS is not a specific disease, but rather a collection of symptoms, which may be exacerbated by certain foods or stress. Symptoms of IBS may vary, but often include:

  • bloating
  • gas
  • constipation, diarrhea, or both
  • cramping
  • abdominal pain

The gastrocolic reflex may be strengthened in those with IBS by the amount and types of food they eat. Common trigger foods include:

  • wheat
  • dairy
  • citrus fruits
  • high-fiber foods, such as beans or cabbage

While there’s no cure for IBS, treatments to help relieve symptoms may include the following lifestyle changes:

  • exercising more
  • limiting caffeine
  • eating smaller meals
  • avoiding deep-fried or spicy foods
  • minimizing stress
  • taking probiotics
  • drinking plenty of fluids
  • getting enough sleep

If symptoms don’t improve with lifestyle changes, your doctor may prescribe medication or recommend counseling. While IBS is primarily a benign condition, if more serious symptoms present, you should seek immediate medical attention to rule out other conditions, such as colon cancer. Those symptoms include:

  • unexplained weight loss
  • diarrhea that wakes you from your sleep
  • rectal bleeding
  • unexplained vomiting or nausea
  • persistent stomach pain that’s not alleviated after passing gas or having a bowel movement

Inflammatory bowel disease (IBD)

If you find yourself frequently having bowel movements right after eating, another underlying cause could be IBD (Crohn’s disease or ulcerative colitis). While Crohn’s disease can involve any part of your gastrointestinal tract, ulcerative colitis affects only your colon. Symptoms may vary and change over time. Other symptoms of IBD may include:

  • diarrhea
  • abdominal cramps
  • blood in your stool
  • fever
  • fatigue
  • loss of appetite
  • weight loss
  • feeling as if your bowels aren’t empty after a bowel movement
  • urgency to defecate

While it’s not clear what causes IBD, it’s thought to be influenced by a combination of factors, including your immune system, genetics, and the environment. In some cases, both Crohn’s disease and ulcerative colitis can lead to life-threatening complications, so seeking treatment as soon as possible is important. Treatment may include:

  • dietary changes
  • medications
  • surgery

Most babies have an active gastrocolic reflex that causes them to have a bowel movement immediately after eating — or even while eating — for their first few weeks of life. This is especially true for breastfed babies and is perfectly normal. Over time, the reflex becomes less active and the time between eating and their stools will decrease.

If you occasionally find yourself suddenly needing to defecate soon after eating, there’s probably nothing to worry about. If, however, it becomes a regular occurrence, you should seek medical treatment to try to determine the underlying cause and find effective treatment options.