A gastroenterologist commonly helps patients manage two bowel conditions: irritable bowel syndrome, or IBS, and inflammatory bowel disease, or IBD. Each of these affects the bowels but does so in different manners. The two disorders can share similar symptoms, leading to challenges in diagnosis in some instances.

Luckily, the experts at the Nebraska Medicine Inflammatory Bowel Disease Center can help you determine your condition and the best means of treating it. Keep reading for a dive into the differences between IBS and IBD, why they matter and how you can use them to help your health care provider diagnose and treat you.

Irritable bowel syndrome

IBS is a common, chronic, and complex condition described as a disorder of the gut-brain interaction – the two-way physical and chemical link that connects your gut to your brain and vice versa. There are three types of IBS:

• IBS – Diarrhea (IBS-D)
• IBS – Constipation (IBS-C)
• IBS – Mixed Type (IBS-M)

Primary symptoms of IBS can include:

• Gas
• Cramps
• Bloating
• Abdominal pain
• Diarrhea, constipation, or both
• Symptom association (improvement or worsening) with bowel movements

Inflammatory bowel disease

IBD is a chronic condition that includes both Ulcerative Colitis and Crohn's disease. Health care providers typically characterize IBD by inflammation in the GI tract. Patients with IBD have a genetic predisposition, and for reasons we do not clearly understand, the immune system becomes activated to send inflammatory cells to parts of the GI tract.

IBD includes several different conditions like:

• Ulcerative colitis (UC) – causes mucosal inflammation limited to the colon and doesn't involve the small intestine.
• Crohn’s disease (CD) – causes patchy inflammation of the intestinal mucosa and can affect any part of your GI tract.
• Indeterminate colitis – a type of IBD that’s neither UC nor CD but shares many typical symptoms with both forms.

Symptoms can vary depending on the location of the inflammation. There are times of active IBD – flares – with symptoms and then times of remission, where little to no symptoms are present. With that said, symptoms of IBD can include:

• Rectal bleeding and/or bloody stools
• Abdominal pain
• Diarrhea
• Constipation
• Bowel urgency
• Gas
• Bloating
• Loss of appetite and weight loss
• Fatigue

Telling IBD apart from IBS

It can be challenging for health care providers to tell IBD apart from IBS because both conditions share many similar patient-reported symptoms. Additionally, it's not uncommon for patients with IBD to also have IBS. Providers rely on a detailed history, physical exam and appropriate testing to differentiate between IBS and IBD.

Certain symptoms help to distinguish between IBS and IBD (or something else). IBS is not typically associated with:

• Rectal bleeding
• Systemic signs of illness – including significant weight loss
• Laboratory evidence of inflammation – from CRP, ESR or fecal calprotectin tests
• Abnormal findings on a colonoscopy

The inflammation caused by IBD can cause the symptoms listed above and others not present in patients with IBS, like:

• Anemia
• Joint pain
• Rashes
• Eye inflammation

Treating IBS vs. IBD

While we have yet to develop a cure for either IBS or IBD, both are treatable through different methods. Both conditions benefit from a multidisciplinary approach. If you have IBS, you and your provider will work to treat your symptoms and avoid triggers. With IBD, therapy aims to treat inflammation to minimize long-term damage.

Managing IBS symptoms

Your health care provider will typically prescribe methods of helping you manage your IBS based on your specific symptoms. Anti-diarrheal and constipation medications can help in addition to other therapies, such as:

• Dietary changes – one of the most common treatments for IBS is adopting the FODMAP diet, which eliminates foods that frequently trigger IBS and promotes gastrointestinal water secretion and fermentation in the colon.
• Medicines – certain medications like antispasmodics can help relieve intestinal spasms.
• Therapy and antidepressants – reducing stress through psychotherapy and/or antidepressants or antianxiety medicines can decrease IBS flares.

Controlling Inflammation from IBD

As previously mentioned, IBD treatment aims to manage your body's inflammation and repair any damage caused by it. Your provider will generally use medications to address this inflammation. Occasionally, surgery is a necessary part of the treatment plan to remove damaged tissue or treat complications.

The medicines providers typically use to address IBD include:

• Biologic Medications – can help reduce intestinal inflammation.
• Immunomodulators – reduce your immune system's responses that contribute to continuous inflammation.
• Corticosteroids – while experts advise against using corticosteroids long-term, they can help minimize flares and better regulate inflammation in the short term.