If you’ve been dealing with recurring stomach pain, bloating and unpredictable bathroom habits, you might’ve found yourself wondering: Could this be IBS? You’re not alone – irritable bowel syndrome affects an estimated 10 to 15 percent of people worldwide, yet many go undiagnosed. Understanding how to test for IBS may lead you to the answers you need.
What is IBS?
Irritable bowel syndrome, or IBS, is a functional gastrointestinal disorder – meaning your digestive tract looks normal, but doesn’t always work the way it should.
Doctors often classify it into these subtypes:
- IBS-C: constipation-predominant
- IBS-D: diarrhea-predominant
- IBS-M: diarrhea and constipation
- IBS-U: unclassified
The symptoms can be frustrating: cramping, bloating, gas and changes in your stool. But the good news is that IBS doesn’t cause permanent damage to the intestines or lead to more serious diseases.
If you have symptoms of IBS but are unsure if you have the condition or another gastrointestinal disorder, make an appointment with a gastroenterologist. Even if you don’t have IBS, working with a GI doctor can help you relieve your symptoms.
How to test for IBS
No single test can diagnose you with IBS. Instead, a diagnosis relies on a combination of symptom history, physical exam and ruling out other conditions.
Start with a doctor’s visit
Your provider will begin with a thorough medical history and symptom review. They may ask about:
- When your symptoms started
- What makes them better or worse
- Your typical bowel patterns
- Triggers like your diet, stress levels and medications
Being honest with your answers will provide details to help them see the whole picture.
Rome IV criteria
To standardize IBS diagnosis, doctors use guidelines called the Rome IV criteria, which focus on symptoms over time. According to this framework, you may have IBS if:
- You’ve had abdominal pain at least one day per week in the last three months
- Pain is associated with defecation, or a change in stool frequency or form
- Symptoms began at least six months ago
Rule out other conditions
IBS symptoms can overlap with other GI issues, including inflammatory bowel disease (IBD), celiac disease or colon cancer, so your provider may order tests to rule out other conditions:
- Blood tests to check for inflammation or anemia
- Stool tests to look for infections or inflammation markers
- Celiac screening (especially if you have diarrhea and fatigue)
In some cases, colonoscopy or imaging studies may be done, especially if you have red flags like:
- Unexplained weight loss
- Rectal bleeding
- Family history of colon cancer or IBD
- Onset of symptoms after age 50
A diagnosis of exclusion
If all your tests come back normal and your symptoms match the Rome IV criteria, your provider may give you a diagnosis of IBS.
While that might sound vague, it’s a structured, evidence-based process. In fact, updated guidelines emphasize that a positive diagnosis based on criteria (rather than endless testing) is safe and effective.
The role of food and stress
While they’re not formal diagnostic tools, many people find that tracking their diet and stress levels helps uncover patterns. For example, some patients discover that FODMAPs (certain types of carbohydrates) or lactose intolerance trigger symptoms.
Your doctor may refer you to a registered dietitian who specializes in IBS to help you safely manage these food sensitivities.
How we can help
Getting tested for IBS might feel overwhelming, but the process is pretty streamlined – and it starts with a conversation. If you’re dealing with chronic digestive issues, don’t try to self-diagnose or tough it out.
Start with an appointment with a gastroenterologist. A proper diagnosis can give you peace of mind and open the door to treatment options that can make a real difference in your daily life.
Learn about the gastroenterology and digestive health services we offer at Mercy Health.
