Is It IBS or Appendicitis: How to Tell the Difference

Appendicitis symptoms require immediate medical attention

In some people, the pain from irritable bowel syndrome (IBS) can be very severe—so severe you may wonder if it is IBS or appendicitis. Telling the difference between IBS gas pain and appendicitis is not easy. Even healthcare providers can have difficulty differentiating them based on symptoms alone.

Appendicitis is caused by an inflamed appendix and requires immediate medical attention. This article discusses the differences between IBS and appendicitis, testing for each condition, and symptoms you should not ignore.

Mid adult woman holding stomach
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What Is Appendicitis?

Appendicitis is a serious health condition in which the appendix becomes inflamed and fills with pus. This may happen due to a blockage caused by fecal matter, a swollen lymph node, a foreign object, or in rare cases, a tumor.

When appendicitis occurs, the appendix needs to be removed immediately via an appendectomy to prevent it from bursting, as this can lead to life-threatening complications.

When an appendix ruptures, its contents can spill into your abdominal cavity, leaving you at risk for a severe and potentially lethal infection known as peritonitis. Although the ultimate treatment for a ruptured appendix is usually an appendectomy, your healthcare provider may first start you on a course of antibiotics to reduce the risk of postoperative infection.

Symptoms of Acute Appendicitis

There are several ways to tell if you have acute appendicitis and need immediate medical attention. The first is that the onset of pain is often abrupt and centered around the belly button.

Among the other signs of acute appendicitis are:

  • Pain that worsens and moves to the lower right part of your abdomen
  • Pain that worsens with movement or coughing
  • Loss of appetite
  • Nausea
  • Vomiting
  • Low fever
  • Chills

IBS vs. Appendicitis

One of the main clues that appendicitis is involved is that the pain will migrate from the navel to the right lower quadrant of the abdomen. With IBS, the pain tends to be centered in the middle of the abdomen nearer to the stomach.

Risk of Unnecessary Surgery

Because the complications of acute appendicitis are so serious, surgeons typically err on the side of caution and choose to remove the appendix of anyone whose symptoms indicate appendicitis.

This leads to a high rate of what is called a "negative appendectomy," which is the removal of a non-inflamed appendix. The rate of negative appendectomies is approximately 15%, even with the use of modern diagnostic technology.

Because the symptoms of appendicitis and IBS overlap, people with IBS appear to be at a higher risk for unnecessary surgeries in general, including negative appendectomies. Research suggests that this may be because people with IBS are more likely to seek treatment and tend to be more anxious than those without.

"Chronic Appendicitis"

One of the main differences between IBS and appendicitis is that the former is chronic and the latter is acute. While people with IBS can have acute outbreaks of symptoms, the disease tends to be something they live with on an ongoing basis.

However, there is a small group of scientists who argue that some people have chronic appendicitis, otherwise known as recurrent appendicitis, appendicopathy syndrome, or neurogenic appendicopathy.

Chronic appendicitis is not widely recognized in the medical community and even those who endorse the theory acknowledge that it is rare. It is theorized that the condition is related to the partial or intermittent obstruction of the appendix.

If such a condition were to exist, it could very well masquerade as IBS. Both syndromes involve recurrent abdominal pain (often worsened by a large meal) and chronic diarrhea, constipation, or both.

The only differentiating factor may be that the recurring pain is in the lower right corner of the abdomen in people with chronic appendicitis.

Telling the Difference

Given that many IBS patients undergo unnecessary surgery, most experts strongly advise against an appendectomy for a person who has IBS—unless there are signs of acute appendicitis.

This typically involves a battery of tests to confirm that appendicitis is involved, including:

If IBS is suspected, colonoscopy or endoscopy are sometimes recommended alongside tests to check for lactose intolerance and bacterial overgrowth.

A Word From Verywell

It is important to note that the symptoms and severity of appendicitis can vary dramatically from one person to the next. If you suspect your appendix is the cause of your symptoms, call your healthcare provider immediately. Do not wait.

If your appendix were to rupture, the pain may ease up but only temporarily. In addition to worsening pain, your abdomen will be very sensitive to the touch and all of the aforementioned symptoms will re-emerge, but invariably worse.

Even if your pain turns out to be IBS (or some other condition), it is better to be safe than sorry.

Frequently Asked Questions

  • Can IBS be confused with appendicitis?

    Yes. In fact, research shows people with IBS are twice as likely to have an unnecessary appendectomy based on symptoms.

  • Can you poop when you have appendicitis?

    Possibly, but maybe not. One of the symptoms of appendicitis is constipation, however, another symptom is diarrhea. Being able to poop does not rule out appendicitis.

  • Do I have trapped gas or appendicitis?

    Trapped gas and appendicitis can have similar symptoms. Typically, appendicitis pain either travels from the navel to the right lower quadrant of the abdomen or is only felt in the lower right abdomen. Gas pain can also migrate, however, it tends to be felt in different parts of the abdomen.

  • What does appendicitis feel like at the beginning?

    Sudden pain in the lower right quadrant of the abdomen is usually the first sign of appendicitis. The pain may also begin near the navel and travel to the lower right side. The pain often worsens if you cough, walk, or make other quick movements. Other symptoms of appendicitis include nausea, vomiting, loss of appetite, low-grade fever, constipation, diarrhea, abdominal bloating, and gas.

  • How long can you have appendicitis symptoms before it bursts?

    An infected appendix can rupture in as little as 48 to 72 hours. If you experience symptoms of appendicitis, seek immediate medical treatment.  

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Medline Plus. Appendicitis.

  2. Longstreth, G. Avoiding unnecessary surgery in irritable bowel syndrome. Gut. 2007;56:608-610. doi:10.1136/gut.2006.115006

  3. De Kok H. Is there an overlap between irritable bowel syndrome and appendicopathy syndrome? A mew theory. Med Hypotheses. 2010;75:501-504. doi:10.1016/j.mehy.2010.07.005

  4. Machado NN, Machado NO. Neurogenic appendicopathy: A historical and contemporary review. World J Colorect Surg. 2014;4(4).

  5. Patel N, Shackleford K. Irritable bowel syndrome. In: StatPearls [Internet].

  6. Lu CL, Liu CC, Fuh JL, et al. Irritable bowel syndrome and negative appendectomy: a prospective multivariable investigation. Gut. 2007;56(5):655–60. doi:10.1136/gut.2006.112672

  7. Johns Hopkins Medicine. Appendicitis.

  8. Mayo Clinic. Appendicitis.

By Barbara Bolen, PhD
Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome.