Colonic Transit Study

A Colonic Transit Study is a simple X-ray test that measures how long it takes for food to travel through your colon (large intestine). This helps your doctor determine if your colon is moving too slowly, which is a cause of severe constipation.

Why is this test done?

This test is used to:

• Diagnose slow transit constipation.
• Identify the specific region of the colon where the delay is occurring.
• Rule out a physical blockage if other tests are normal.

How do I prepare for the test?

• You will be asked to stop certain medications (like laxatives, opioids) for a few days before and during the test.
• Follow your doctor’s specific dietary instructions.

What happens during the procedure?

1. Day 1: You will swallow a single capsule containing many small, harmless plastic markers that show up on an X-ray.
2. X-Rays: You will return for abdominal X-rays on specific days (usually Day 5). You must not use laxatives between X-rays.
3. The radiologist will count the number of markers remaining in your colon on each X-ray. If most markers are still present after 5 days, it indicates slow transit constipation.

After the Procedure

There are no restrictions after the X-rays are complete. Your doctor will discuss the results with you at your next appointment.

Are there any risks?

The radiation exposure from the X-rays is very low. The markers are inert and will pass harmlessly out of your body in your stool.