When you are dealing with stomach pain, the internet is full of possible causes, sending most people down rabbit holes of possibilities. Two digestive health conditions, irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD), even share a word in their name and a host of similar symptoms.

“IBS and IBD sound very similar,” says Loren Rabinowitz, MD, a gastroenterologist with Beth Israel Lahey Health in Boston. “It isn't surprising to us that patients are often confused, and a lot of the symptoms can overlap.”

Furthermore, the two are not necessarily exclusive from each other.

A systematic review published in the Journal of Gastroenterology in 2012 found that up to 40 percent of people with IBD also had IBS symptoms — statistics that experts still quote today.

However, IBS and IBD have some key differences in symptoms and treatments. Here is what to look for.

Quality of Life vs. Serious Risk

IBS can cause diarrhea or constipation, with some patients possibly experiencing a mixture of both. Some people with IBS may also have other distressing symptoms like abdominal pain.

“IBS is a syndrome, which is really just a collection of symptoms and not a specific pathology or a specific disease,” says Jesse Stondell, MD, the program director of the department of gastroenterology at the University of California in Davis Health Medical Center. “IBS is a quality-of-life problem and tends not to be dangerous. It doesn't shorten life spans or put people in the hospital.”

IBS is more common than IBD, affecting between 25 and 45 million people in the United States, according to the International Foundation for Gastrointestinal Disorders, or about 10 to 15 percent of the population.

IBS is also more common in women than men, accounting for two out of every three cases.

Meanwhile, only an estimated 3.1 million adults in the United States have been diagnosed with either Crohn’s disease or ulcerative colitis, according to the Centers for Disease Control and Prevention, accounting for 1.3 percent of the population.

Someone with IBD will have Crohn’s disease or ulcerative colitis, which are chronic, destructive autoimmune gut diseases. Crohn's disease can impact the digestive tract anywhere from the mouth to the rectum, while ulcerative colitis causes inflammation in the colon.

Like with IBS, someone with IBD may experience abdominal pain and diarrhea, but they can also have rectal bleeding and iron deficiency anemia. People can unintentionally lose weight and be constantly tired, which may be the first symptoms they experience before feeling any pain.

“IBD, when severe, can be quite serious and may even require surgery in some cases, which is not the case with IBS,” says Dr. Rabinowitz.

Why Do IBS and IBD Get Confused for the Other?

Abdominal pain and diarrhea can occur for both IBS and IBD, and diarrhea for more than four weeks is a sign to have a conversation with your primary care physician and receive some testing.

Stress is also a trigger for patients with IBS or IBD and can cause symptoms to flare, making it more challenging to identify which condition someone has, says Rabinowitz.

The similarities are not just confusing for everyday people. Doctors have misdiagnosed IBS for IBD or vice versa due to the similar symptoms they share.

One of the most recent studies looking at the overlap between IBS and IBD was published in December 2018 in Inflammatory Bowel Diseases; it found that around 20 percent of patients with Crohn’s disease or ulcerative colitis also manifested IBS symptoms.

Additionally, some patients may describe symptoms that would suggest IBS over IBD.

“Patients who are young can compensate for their disease well,” says Dr. Stondell. “They either just didn't go to the doctor for a long time, or they went to the doctor and the doctor presumed they had IBS without doing an appropriate screen.”

What is known is that women are often misdiagnosed with IBS. Since women have a higher rate of IBS than men in general, doctors defer to it as a default diagnosis and automatically assume that women have IBS, not IBD. A study published in January 2023 in Inflammatory Bowel Diseases found that while the clinical presentation of IBD was similar in both men and women, women had a higher percentage of misdiagnosis than men, which lengthened the time it took for them to get adequate treatment.

How Do I Get Properly Diagnosed?

If you think you may have either IBS or IBD, the first step is to see your primary care doctor and be forthcoming with your symptoms. Doctors have found that sometimes patients cannot always express themselves in a way that can get a doctor to diagnose correctly.

“With young people, a lot of the time, they're not used to describing these things or talking about these things," says Stondell. “They'll show up and say they're having some bowel movement problems, and you have to really work with them to elaborate on exactly what they're feeling and what exactly is happening.”

To ensure you are correctly diagnosed, the Crohn’s & Colitis Foundation suggests these tips:

Share with your doctor any previous medical records, including summaries of visits with other doctors, lab results, and other tests that may have already been performed.
Bring a trusted family member or close friend to your appointment to help you remember information from your visit. In lieu of bringing a third party, you can bring a notepad to record the next steps you may need to take.
Write down questions and the timeline of your symptoms beforehand and bring the list with you to your appointment so you don’t have to worry about forgetting anything important.

“The primary care doctor will take a very careful and detailed history," says Rabinowitz. “It’s to get a better sense of what may be the underlying cause. This is the first and probably most important step.”

Once a doctor has a handle on your history, they can recommend tests and, if needed, specialists to further home in on the problem.

For IBS, a combination of blood, stool, and other tests, along with your health history, will help a doctor get to a diagnosis, according to the National Institute of Diabetes and Digestive and Kidney Diseases.

A diagnosis of IBD includes these tests and others, including a colonoscopy and possibly an endoscopy, which is when you would see a gastroenterologist.

Differences in Treatments for IBS and IBD

For people with IBS and symptoms of diarrhea, lifestyle changes like dietary modifications, such as cutting out certain sugars and increasing fiber, as well as exercising and maintaining a healthy body weight, could be helpful. In addition, prescription medications are available to address symptoms.

In addition to diet and lifestyle changes, people with IBD will be prescribed medication to keep inflammation and symptoms at bay.

“It can be as simple as an oral anti-inflammatory pill that just treats and reduces inflammation,” says Stondell. “But oftentimes, it's a little more complex, where we actually use medicines that try and rein in the overactive parts of that person's immune system because it is an immune disease.”

No matter the diagnosis, the road to treatment can be long, given the chance of misdiagnosis or having to go through several specialists. Persistence is key.

“I always tell my patients, and I tell my friends and family if you have a syndrome and you're concerned about it, the best thing you can do is flag it to a physician,” says Rabinowitz. “If you don't feel well, don't suffer in silence."