Appendicitis happens when your appendix becomes inflamed, likely due to a blockage. In the United States, appendicitis is the most common cause of abdominal pain resulting in surgery. Up to 9 percent of Americans experience it at some point in their lives.
The appendix is a small pouch attached to the intestine located in your lower-right abdomen. When your appendix becomes blocked, bacteria can multiply inside it, which can lead to the formation of pus and swelling, which can cause painful pressure in your abdomen.
Left untreated, appendicitis can cause your appendix to burst. This can cause bacteria to spill into your abdominal cavity, which can be serious and sometimes fatal if untreated.
Types of Appendicitis
Acute Appendicitis
- The most common form
- Sudden and severe, often developing over 24 hours
- Occurs most frequently in people ages 10–30
- Slightly more common in males
- Requires immediate medical treatment to prevent rupture
- Accounts for the majority of appendicitis cases
Chronic Appendicitis
- Much less common
- Symptoms may be milder and come and go over weeks, months, or even years
- Can be difficult to diagnose
- Often discovered only when symptoms progress into acute appendicitis
What Appendicitis Feels Like
Pain is the primary symptom. It often begins as a dull discomfort around the belly button or upper abdomen and then shifts to the lower right side.
You may notice pain that:
- Starts suddenly
- Worsens with movement, coughing, or deep breathing
- Becomes severe enough to wake you from sleep
- Feels different from any abdominal pain you’ve had before
- Intensifies over several hours
Additional symptoms may include:
- Nausea or vomiting
- Loss of appetite
- Indigestion
- Abdominal swelling
- Low-grade fever
Less commonly, bowel-related symptoms may appear:
- Diarrhea
- Constipation
- Difficulty passing gas
- A constant urge to have a bowel movement
Important: If you are constipated and suspect appendicitis, do not use laxatives or enemas. These can increase the risk of rupture.
When to Seek Medical Attention
Appendicitis can progress quickly and is considered a medical emergency. Contact a provider immediately if you or your child has lower-right abdominal pain along with any of the symptoms above. Your appendicitis is diagnosed by your provider by doing the following:
- A detailed conversation about your symptoms
- A physical exam, including checking for tenderness in the lower right abdomen
- Possible abdominal or rectal exams
Because no single test confirms appendicitis, your provider may order imaging or lab work such as:
- Blood tests
- Urinalysis
- Ultrasound
- CT scan
Appendicitis is diagnosed when symptoms, exam findings, and test results point to inflammation and no other cause explains the pain.