Irritable bowel syndrome (IBS) and diverticulitis are conditions that affect the digestive system. While many of their symptoms are similar, there are some key differences.

A person may have IBS if they consistently experience abdominal pain and bloating, and have problems with bowel movements, such as diarrhea and constipation.

Diverticulitis can present with similar symptoms, but the pain tends to be more severe and urgent, and patients might have additional symptoms of fever, nausea, vomiting, and increased urinary urgency.

Researchers do not fully understand what causes IBS and diverticulitis. Doctors often recommend diet and lifestyle changes to help manage each condition.

This article discusses what IBS and diverticulitis are in more detail, including their symptoms, causes, treatment, and prevention.

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IBS is one of the most common gastrointestinal diseases. It describes a range of gastrointestinal symptoms, involving abdominal discomfort and changes in bowel habits, that vary between individuals.

Doctors may make an IBS diagnosis if someone has been experiencing these symptoms at least once a week over the last 3 months and the symptoms first started at least 6 months ago.

Diverticulitis occurs when the diverticula become inflamed.

Diverticula are small sacs or pouches that develop in the large intestine lining, when this happens a person has diverticulosis. A person can have diverticulosis and never develop diverticulitis.

Diverticular disease is a term that describes diverticulitis and diverticulosis.

While IBS and diverticulitis can cause similar symptoms, they are not the same. Diverticulitis may cause a wider range of symptoms.


IBS symptoms include:

The symptoms can vary between individuals and depend on the type of IBS a person has.


Diverticulitis symptoms include:

Complications of diverticulitis include:

According to the United Kingdom’s National Health Service (NHS), a person may also experience urinary issues due to the inflamed part of the colon pushing onto the bladder. These may include needing to urinate more often than usual and pain while urinating.

Experts do not fully understand the causes of IBS and diverticulitis. However, researchers have linked some risk factors with each condition.


Researchers believe problems with the gut-brain connection may cause IBS. In particular, if a person has experienced:

Researchers also suggest that a person’s genes may contribute to their likelihood of developing IBS.


Several factors may cause diverticulitis, but more research is necessary to understand the exact causes.

Some possible causes include:

  • Genes: Researchers have identified some genes that can increase the risk of a person developing diverticular disease.
  • Bacteria: Changes in the gut microbiota or bacteria becoming trapped in a pouch in the colon can increase the risk of diverticulitis.
  • Immune system: If a person has a condition that affects their immune system and causes chronic inflammation, they may develop diverticulitis symptoms.
  • Structural abnormalities: This may include problems with the connective tissue, muscles, or nerves in a person’s colon.

Some risk factors include:

When someone has IBS or diverticulitis, treatments typically include dietary and lifestyle changes, in addition to medication.


People may find the following are effective in managing their symptoms:

Additionally, some supplements, such as peppermint oil, may be beneficial for people with IBS. However, it is important to note the Food and Drug Administration (FDA) does not regulate supplements; consequently, they are not held to the same rigorous safety testing standards as medications.

Medications a doctor may recommend vary depending on the type of IBS a person has and their individual circumstances, but they may include:


When a person has received a diverticulitis diagnosis, the severity of their symptoms determines their treatment plan.

Generally, for milder symptoms, a person may need to:

  • increase their intake of high fiber foods
  • take anti-inflammatory medications
  • take probiotics

Before taking probiotics, a person should speak to their doctor first. They can determine whether probiotics may help and discuss any potential drug interactions.

If complications are causing more severe symptoms, a person may need to take antibiotics and consume a clear liquid diet for some time. Doctors may also recommend medications to help manage pain.

In some cases, such as when a person has developed a complication resulting from diverticulitis, the condition may require surgery to remove the diverticula or part of the colon.

There are some preventive measures a person can take to reduce their symptoms of IBS and diverticulitis.


The following preventive measures may be useful for managing symptoms:

  • eating more fiber
  • avoiding gluten
  • following a FODMAP diet
  • increasing physical activity
  • reducing stress as much as possible
  • getting enough sleep


Some methods that may help prevent diverticulitis include:

IBS and diverticulitis cause symptoms that affect the digestive system. They may share some symptoms, such as constipation and diarrhea. However, unlike IBS, diverticulitis can cause fever, chills, and vomiting. It may also cause more sudden and severe pain than IBS.

Researchers do not fully understand the exact causes of IBS and diverticulitis, though a range of genetic and lifestyle factors may increase a person’s risk of developing either condition.

A person should speak with a doctor or another healthcare professional if they experience any symptoms of IBS or diverticulitis. They can make an accurate diagnosis and recommend appropriate treatment.