Understanding how your digestive system moves food through your body is essential when something goes wrong. Gastrointestinal motility disorders affect the coordinated muscle movements that push food from your mouth through your digestive tract and out of your body, causing a range of uncomfortable symptoms that can significantly impact your daily life.

Introduction: Who Should Seek Diagnostics

If you experience ongoing digestive symptoms that interfere with your daily activities, it may be time to consider diagnostic testing for a gastrointestinal motility disorder. These conditions occur when the muscles or nerves in your digestive tract do not work together as they should, disrupting the normal movement of food and waste through your system.^[1]

You should consider seeking medical evaluation if you have persistent symptoms such as severe constipation that does not improve with usual treatments, recurrent vomiting or nausea, difficulty swallowing food or liquids, chronic heartburn, or unexplained weight loss. Other warning signs include feeling full very quickly after starting a meal, ongoing bloating and abdominal discomfort, chronic diarrhea, or problems controlling your bowel movements.^[2][4]

These symptoms can affect any part of your digestive tract, from the tube that connects your mouth to your stomach, called the esophagus, all the way through your stomach, small intestine, large intestine, and down to your rectum. The location and type of symptoms you experience often give your doctor important clues about which part of your digestive system may be affected.^[8]

It is particularly important to seek diagnostic testing if your symptoms are interfering with your ability to maintain proper nutrition, causing you to miss work or school regularly, or significantly reducing your quality of life. Some people find that their symptoms make it difficult to engage in physical activities or maintain their usual social routines. When digestive problems reach this level of impact, a thorough diagnostic evaluation can help identify the underlying cause and guide appropriate treatment.^[7]

Classic Diagnostic Methods

Diagnosing a gastrointestinal motility disorder typically begins with a comprehensive evaluation by your doctor. This starts with a detailed discussion of your medical history, a review of your current symptoms, and a physical examination. Your doctor will ask specific questions about when your symptoms occur, what makes them better or worse, and how they affect your daily life. They will also review any medications you are taking, as certain drugs can affect digestive motility.^[4]

After this initial evaluation, your doctor will often recommend diagnostic tests to examine the structure and function of your digestive tract. The first step is usually to rule out any structural problems, such as blockages or abnormalities in the shape of your digestive organs. This might involve procedures like endoscopy, where a thin, flexible tube with a camera is inserted through your mouth or rectum to visually inspect the inside of your digestive tract, or colonoscopy, which examines the large intestine.^[4]

Tests for the Esophagus and Swallowing

If you have difficulty swallowing or chest pain, your doctor may recommend tests that specifically evaluate how your esophagus functions. One common test is esophageal manometry, which measures the strength and coordination of the muscle contractions in your esophagus. During this test, a thin, flexible tube about the size of a smartphone power cord is carefully placed through your nose and guided down into your esophagus. You will then be asked to swallow small amounts of water while sensors on the tube measure the pressure and pattern of muscle contractions.^[5]

Another tool is called EndoFLIP, a newer technology that uses a catheter with a small balloon attached. This device is placed in your mouth while you are asleep under sedation. The balloon is slowly inflated to stimulate contractions, allowing doctors to observe how the muscles and the ring-shaped valve at the bottom of your esophagus respond.^[4]

If you experience heartburn or acid reflux, your doctor might recommend pH monitoring tests. These tests measure the amount and frequency of acid backing up from your stomach into your esophagus. There are different types of pH monitoring. One version involves attaching a small wireless device to the wall of your esophagus during an endoscopy procedure. This device measures acid levels over two days. Another type uses a thin catheter placed through your nose that stays in place for 24 hours while connected to a small data recorder you carry with you.^[5]

Tests for the Stomach

When symptoms suggest problems with how your stomach empties food into your small intestine, specialized tests can measure this process. One option is a gastric emptying scan, which involves eating a small meal that contains a tiny amount of radioactive material that is safe and does not cause any harm. A special camera then tracks how quickly the food moves out of your stomach over several hours.^[2]

A more advanced option is the SmartPill wireless motility capsule. This is a pill-sized sensor that you swallow with water. As it travels through your digestive system over approximately five days, it measures temperature, acid levels, and pressure. It also records how long it takes for the capsule to move through your stomach, small intestine, and colon. The device transmits this information to a small receiver you carry with you. This test can help diagnose several conditions including delayed stomach emptying, called gastroparesis, as well as problems with intestinal movement and constipation.^[7][13]

Tests for the Intestines

If your symptoms point to problems in your small or large intestine, different diagnostic approaches may be needed. Breath tests can evaluate whether your body properly absorbs certain sugars and starches. These tests can also detect small intestinal bacterial overgrowth, a condition where too many bacteria grow in the small intestine, causing symptoms like bloating, diarrhea, and excessive gas. For this test, a tube may be inserted through an endoscope to collect fluid from your small intestine, which is then examined for excessive bacteria or fungus.^[7][13]

Another test for intestinal problems is video capsule endoscopy, where you swallow a pill-sized camera that takes thousands of pictures as it travels through your small intestine. These images help doctors look for sources of bleeding or signs of inflammatory conditions. The capsule passes naturally out of your body after completing its journey through your digestive tract.^[5]

Tests for the Colon and Pelvic Floor

When symptoms involve the lower part of your digestive tract, tests may focus on your colon and the muscles involved in bowel movements. Anorectal manometry explores how well the muscles in your rectum and anus function. This test measures muscle strength and coordination during squeezing and relaxing, helping to diagnose conditions that cause constipation or difficulty controlling bowel movements.^[2]

Another test called a Sitzmark study can help evaluate constipation. You swallow a capsule containing small markers that show up on X-rays. Over the next several days, X-rays track how quickly these markers move through your colon, revealing whether constipation is due to slow movement or problems with the muscles used for bowel movements.^[2]

Blood tests and stool tests may also be part of your diagnostic workup. While these do not directly measure motility, they help rule out other conditions that can cause similar symptoms, such as thyroid problems, infections, inflammation, or nutritional deficiencies.^[6]

Diagnostics for Clinical Trial Qualification

When patients with gastrointestinal motility disorders are considered for participation in clinical trials, specific diagnostic criteria must be met to ensure that study participants have the condition being investigated. Clinical trials test new treatments, medications, or procedures, and having a clear, confirmed diagnosis is essential for determining whether a potential treatment is effective.^[10]

The diagnostic methods used to qualify patients for clinical trials are typically the same standard tests used in regular clinical practice, but they are applied more strictly. For example, if a clinical trial is testing a new medication for gastroparesis, participants would need to have documented evidence of delayed stomach emptying. This would likely require a gastric emptying scan showing that food remains in the stomach longer than normal. The trial protocol might specify exactly how delayed the emptying must be, measured as a percentage of food remaining in the stomach after a certain number of hours.^[8]

For trials studying esophageal motility disorders like achalasia, qualification might require specific findings on esophageal manometry. The test results would need to show characteristic patterns, such as failure of the lower esophageal sphincter to relax properly or absence of normal coordinated contractions along the esophagus. These objective measurements ensure that all participants in the trial truly have the condition being studied.^[6]

Blood tests are often required as part of clinical trial screening to check your overall health and ensure that you do not have other conditions that might interfere with the study. These might include tests to evaluate your liver and kidney function, blood cell counts, and levels of certain nutrients. Some trials also require imaging studies, such as CT scans or ultrasounds, to rule out structural abnormalities or other diseases that might explain your symptoms.^[6]

Clinical trials may also use specialized questionnaires and symptom diaries to document the severity and frequency of your symptoms before treatment begins. These standardized tools help researchers measure whether a treatment improves symptoms over time. You might be asked to record details about your daily symptoms, including pain levels, number of bowel movements, episodes of nausea or vomiting, and how symptoms affect your ability to eat, work, and carry out normal activities.^[10]

The qualification process for clinical trials is more rigorous than standard diagnosis because researchers need to be certain that any improvements seen during the study are due to the treatment being tested, not to other factors. This means that some people who have a motility disorder diagnosed in regular clinical practice might not meet the specific criteria needed to participate in a particular clinical trial. Trial protocols are designed to create a group of participants who are as similar as possible in terms of their disease characteristics, which helps researchers draw more reliable conclusions about whether a treatment works.^[10]