Appendicitis Overview: Causes, Symptoms, and Treatment

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Appendicitis is inflammation of the appendix. The appendix is a small, tube-like structure attached to the first part of the large intestine (also called the colon). It is located in the lower right portion of the abdomen, but it has no known function, and removal of it appears to cause no change in digestive function.

Once appendicitis starts, there is no effective medical therapy, so appendicitis is considered a medical emergency. When treated promptly, most patients recover without difficulty. If treatment is delayed, the appendix can burst, causing infection and even death.

While anyone can get appendicitis, it occurs most often between the ages of 10 and 30.


The cause of appendicitis relates to blockage of the inside of the appendix, known as the lumen. The blockage leads to increased pressure, impaired blood flow, and inflammation. If the blockage is not treated, gangrene and rupture (breaking or tearing) of the appendix can result.

Most commonly, feces blocks the inside of the appendix. Also, bacterial or viral infections in the digestive tract can lead to swelling of lymph nodes, which squeeze the appendix and cause obstruction. Traumatic injury to the abdomen may also lead to appendicitis in a small number of people.

You may be surprised to learn that genetics may be a factor in who gets appendicitis. Appendicitis that runs in families may result from a genetic variant that predisposes a person to obstruction of the appendiceal lumen.

Related: Is Your Abdominal Pain From IBS Or An Appendicitis?


Symptoms of appendicitis may include:

  • Pain in the abdomen, first around the belly button, then moving to the lower right area—this is called migratory abdominal pain
  • Loss of appetite
  • Nausea and vomiting
  • Constipation or diarrhea
  • Inability to pass gas
  • Low fever that begins after other symptoms
  • Abdominal swelling
  • Indigestion

In terms of the abdominal pain of appendicitis (the most common and almost always present symptom), classically the pain intensifies and worsens when moving, taking deep breaths, coughing, or sneezing. The area that is painful becomes very tender to any pressure.

People may also have a sensation called "downward urge," also known as "tenesmus," which is the feeling that a bowel movement will relieve their discomfort. That being said, laxatives should not be taken in this situation.

It is important to understand that not everyone with appendicitis has all the above symptoms. This is why it is critical to see a doctor immediately if you have concerns or any of the above symptoms with abdominal pain.

Also, people with special conditions may not have the set of symptoms above and may simply experience a general feeling of being unwell. Patients with these conditions include:

  • People who use immunosuppressive therapy such as steroids
  • People who have received a transplanted organ
  • People with diabetes
  • People who have cancer or who are receiving chemotherapy
  • Obese people

Pregnant Women

Abdominal pain, nausea, and vomiting are more common during pregnancy and may or may not be signs of appendicitis. Many women who develop appendicitis during pregnancy do not experience the classic symptoms, especially in the third trimester. It is important that a pregnant woman who experiences pain on the right side of the abdomen contact a doctor.

Infants and Children

Infants and young children often cannot, or are limited in their ability to, communicate pain to their parents or doctors. Without a clear history, doctors must rely on a physical exam and less specific symptoms, such as vomiting and fatigue. Toddlers with appendicitis sometimes have trouble eating and may seem unusually sleepy. Children may have constipation, but may also have small stools that contain mucus.

In short, symptoms vary widely among children and are not as classic as those in adults (especially in young children). So if you think your child has appendicitis, contact a doctor immediately.

Related: Treating A Child's Fever

Older People

Older patients tend to have more medical problems than young people. The elderly often experience less fever and less severe abdominal pain than other patients do with appendicitis. Many older adults do not know that they have a serious problem until the appendix is close to rupturing. A slight fever and abdominal pain on one's right side are reasons to call a doctor right away.

All people with special health concerns and their families need to be particularly alert to a change in normal functioning and patients should see their doctors sooner, rather than later, when a change occurs.


To determine if a patient has appendicitis, doctors will use a variety of diagnostic tools.

Medical History 

Asking questions to learn the history of symptoms and a careful physical examination are key in the diagnosis of appendicitis. The doctor will ask many questions to understand the nature, timing, location, pattern, and severity of pain and symptoms. Any previous medical conditions and surgeries, family history, medications, and allergies are important information to the doctor. Use of alcohol, tobacco, and any other drugs should also be mentioned. This information is considered confidential and cannot be shared without the permission of the patient.

Physical Examination

Before beginning a physical examination, a nurse or doctor will usually measure vital signs: temperature, pulse rate, breathing rate, and blood pressure. Usually, the physical examination proceeds from head to toe. Many conditions such as pneumonia or heart disease can cause abdominal pain. Generalized symptoms such as fever, rash, or swelling of the lymph nodes may point to diseases that wouldn't require surgery.

Examination of the abdomen helps narrow the diagnosis. Location of the pain and tenderness is important—pain being a symptom described by a person and tenderness being the response to being touched.

Two signs, called peritoneal signs, suggest that the lining of the abdomen is inflamed and surgery may be needed:

  • Rebound tenderness: When the doctor presses on a part of the abdomen and the person feels more tenderness when the pressure is released than when it is applied
  • Guarding: The tensing of muscles in response to touch

The doctor may also move the patient's legs to test for pain on flexion of the hip (called the psoas sign), pain on internal rotation of the hip (called obturator sign), or pain on the right side when pressing on the left (calling Rovsing's sign). These are valuable indicators of inflammation, but not all patients have them.

Laboratory Tests

Blood tests are used to check for signs of infection, such as a high white blood cell count. Blood chemistries may also show dehydration or fluid and electrolyte disorders. Urinalysis is used to rule out a urinary tract infection. Doctors may also order a pregnancy test for women of childbearing age or perform a pelvic examination to rule out gynecological causes for the pain. 

Imaging Tests

X-rays, ultrasound, and computed tomography (CT) scans can produce images of the abdomen. Plain x-rays can show signs of obstruction, perforation (a hole), foreign bodies, and in rare cases, an appendicolith, which is hardened stool in the appendix.

Ultrasound may show appendiceal inflammation and can diagnose gallbladder disease and pregnancy.

By far the most common test used, however, is the CT scan. This test provides a series of cross-sectional images of the body and can identify many abdominal conditions and facilitate diagnosis when the clinical impression is in doubt. Sometimes, a magnetic resonance imaging (MRI) is used to assist in a doctor's evaluation for appendicitis in women who are pregnant (since radiation is given during a CT scan but not an MRI). 

In selected cases, particularly in women when the cause of the symptoms may be either the appendix or an inflamed ovary or fallopian tube, laparoscopy may be necessary. This procedure avoids radiation but requires general anesthesia. A laparoscope is a thin tube with a camera attached that is inserted into the body through a small cut, allowing doctors to see the internal organs. Surgery can then be performed laparoscopically if the condition present requires it.​

Related: Tests Used to Diagnose Abdominal Pain


Once appendicitis is diagnosed, it needs to be treated right away.


Acute appendicitis is treated by surgery to remove the appendix. The operation may be performed openly through a standard small incision in the right lower part of the abdomen, or it may be performed using a laparoscope, which requires three to four smaller incisions.

If other conditions are suspected in addition to appendicitis, they may be identified using laparoscopy. In some patients, laparoscopy is preferable to open surgery because the incision is smaller, recovery time is quicker, and less pain medication is required. The appendix is almost always removed, even if it is found to be normal. With complete removal, any later episodes of pain will not be attributed to appendicitis.

Recovery from appendectomy takes a few weeks. Doctors usually prescribe pain medication and ask patients to limit physical activity. Recovery from laparoscopic appendectomy is generally faster, but limiting strenuous activity may still be necessary for three to five days after a laparoscopic surgery (and 10 to 14 days after an open surgery).

Most people treated for appendicitis recover excellently and rarely need to make any changes in their diet, exercise, or lifestyle.

Antibiotic Therapy

If the diagnosis is uncertain, people may be watched and sometimes treated with antibiotics. This approach is taken when the doctor suspects that the patient's symptoms may have a nonsurgical or medically treatable cause. If the cause of the pain is infectious, symptoms resolve with intravenous antibiotics and intravenous fluids.

Occasionally the body is able to control an appendiceal perforation by forming an abscess. An abscess occurs when an infection is walled off in one part of the body. The doctor may choose to drain the abscess and leave the drain in the abscess cavity for several weeks. An appendectomy may be scheduled after the abscess is drained.

In general, appendicitis can only be treated with surgery—only in specific people or in children is antibiotic therapy alone considered a possible treatment for appendicitis.


The most serious complication of appendicitis is a rupture. The appendix bursts or tears if appendicitis is not diagnosed quickly and goes untreated. Infants, young children, and older adults are at highest risk. A ruptured appendix can lead to peritonitis and abscess. Peritonitis is a dangerous infection that happens when bacteria and other contents of the torn appendix leak into the abdomen. In people with appendicitis, an abscess usually takes the form of a swollen mass filled with fluid and bacteria. In a few patients, complications of appendicitis can lead to organ failure and death.

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.
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By Sharon Gillson
 Sharon Gillson is a writer living with and covering GERD and other digestive issues.