GI Tract

Motility tests to check for bacterial overgrowth, sugar intolerances, and GI tract transit times are also offered at UCLA.

Breath testing

We can arrange for at-home breath testing. Your UCLA gastroenterologist can use breath testing to check for bacterial overgrowth of the small intestine or check for intolerance to certain sugars.

After your doctor orders a breath test, a breath test kit will be shipped to your home. The kit includes preparation instructions, instructions on how to perform the test, tubes for breath samples, labels, sugar, straw, and a mailing label. Once you have completed the test, a gastroenterologist will interpret the results.

Breath testing is used to diagnose or evaluate: Small intestinal bacterial overgrowth (SIBO), IBS-diarrhea predominant, and sugar intolerances.

If this test has been ordered by your gastroenteologist, and you have questions about how to schedule or prepare for your appointment, please speak with your doctor's office.

Gastric emptying study

This is a test performed by the Nuclear Medicine Department. It measures how long it takes for food to move from the stomach into the small intestine. To prepare, you will need to stop eating or drinking 4 hours before your appointment. During the test, you will be given a protein-based sandwich that has a radioactive tracer. This allows the radiologist to see where the food is in your digestive tract throughout your test. After eating the sandwich, you will lie down and a scanner will take pictures of your abdomen every hour for a total of 4 hours.

Gastric emptying study is used to diagnose or evaluate: Gastric emptying time and gastroparesis.

If this test has been ordered by your gastroenteologist, and you have questions about how to schedule or prepare for your appointment, please speak with your doctor's office.

Sham feed study

The sham feed study is used to check how the Vagus nerve functions. A sham feed is when food is chewed but not swallowed. During a sham feed, the pancreas secretes pancreatic polypeptide into the bloodstream. In this study, pancreatic polypeptide levels are checked with a series of blood draws at different timed intervals.

The sham feed study will be performed by a nurse. The nurse will draw blood from you six different times. To avoid inserting a needle each time, the nurse will place a peripheral IV in your arm. During each blood draw a small amount of blood is drawn (about a teaspoon).

The nurse will draw blood twice and then instruct you to chew and spit your meal into a plastic bag. Once the sham feed is done, the nurse will draw blood four more times at different timed intervals. Once the blood draws have been completed, the nurse will remove the IV and you can return to your usual activities. The test takes about an hour to complete.

The sham feed study is used to evaluate: Vagal nerve function.

Your physician may order one of the following tests. Download prep instructions

• Sham feed study