Key Takeaways
- Acute appendicitis is a sudden inflammation of the appendix that usually worsens quickly.
- It is considered a medical emergency because untreated cases can lead to rupture and serious infection.
- Diagnosis relies on clinical evaluation, lab tests, and imaging rather than a single definitive test.
- Surgical removal of the appendix is the most common treatment, though antibiotics may be used in selected cases.
Overview
Acute appendicitis is a sudden inflammation of the appendix. It typically develops quickly and can worsen over hours to a short period of days. Because untreated appendicitis can lead to serious complications, it is generally treated as a medical emergency that requires prompt evaluation and care.
The Appendix and What Happens in Acute Appendicitis
The appendix is a narrow, tubular structure connected to the large intestine and located in the lower right side of the abdomen. Acute appendicitis most often occurs when the inside of the appendix becomes blocked. This blockage can lead to bacterial overgrowth, inflammation, and swelling.
If inflammation progresses without treatment, blood flow to the appendix can decrease, increasing the risk of rupture. A ruptured appendix can spread infection within the abdominal cavity and may result in life-threatening complications.
Is Acute Appendicitis an Emergency?
Yes. Acute appendicitis is widely regarded as a medical emergency.
Without treatment, the appendix can rupture. Rupture may lead to peritonitis (infection of the abdominal lining), abscess formation, or bloodstream infection. Prompt medical evaluation and treatment reduce the risk of these complications.
Acute vs. Chronic Appendicitis
Acute Appendicitis
- Begins suddenly and progresses quickly
- Symptoms typically worsen over a short period
- Usually requires urgent medical treatment
Chronic Appendicitis
- Considered rare
- Symptoms may be milder and occur intermittently over a longer period
- Still requires medical evaluation, as it can worsen or become acute
Symptoms of Acute Appendicitis
Symptoms can vary, but commonly include:
- Abdominal pain that often begins near the belly button and later moves to the lower right abdomen
- Pain that worsens with movement, coughing, or pressure
- Loss of appetite
- Nausea and vomiting
- Fever
Adults and Children
- Adults often describe increasing pain severity that may change location over time.
- Children may have less typical symptoms and can present with vomiting, fever, or general discomfort.
What Causes Acute Appendicitis?
Acute appendicitis is most often caused by obstruction of the appendix. Documented causes include:
- Hardened stool (appendicolith or fecalith)
- Swelling of lymphatic tissue
- Infection
- Tumors (more commonly reported in adults)
In some cases, the exact cause cannot be clearly identified.
Who Is at Risk?
Acute appendicitis can occur at any age. It is commonly seen in children, adolescents, and young adults. Older adults and pregnant individuals may have atypical symptoms, which can make diagnosis more difficult and increase the risk of complications.
How Acute Appendicitis Is Diagnosed
There is no single test that definitively confirms acute appendicitis. Diagnosis typically involves a combination of the following.
Medical History and Physical Examination
Clinicians assess symptom history and examine the abdomen for tenderness, guarding, or pain with pressure.
Laboratory Tests
Blood tests may show signs of infection or inflammation, such as an elevated white blood cell count. These tests support the diagnosis but do not confirm it on their own.
Imaging Studies
Imaging is commonly used to confirm appendicitis or rule out other causes of abdominal pain. This may include:
- Ultrasound
- CT scan
- MRI (often used during pregnancy)
Treatment for Acute Appendicitis
Surgery (Appendectomy)
Surgical removal of the appendix, called an appendectomy, is the most common and definitive treatment. In many cases, this can be performed using minimally invasive (laparoscopic) techniques.
Antibiotics
In selected cases of uncomplicated appendicitis, antibiotics alone may be considered. However, symptoms may return, and surgery may still be required later.
If the Appendix Has Ruptured
Treatment may involve antibiotics, drainage of infection or abscess, and sometimes delayed surgery once the infection is controlled.
Recovery After Treatment
Recovery depends on:
- Whether surgery was required
- The type of surgery performed
- Whether complications occurred
Some patients may go home the same day after uncomplicated laparoscopic surgery, while others may require a longer hospital stay. Activity restrictions and recovery time vary based on individual circumstances.
Possible Complications If Untreated
If acute appendicitis is not treated, complications can include:
- Rupture of the appendix
- Peritonitis
- Formation of an abdominal abscess
These complications can be serious and often require more extensive medical or surgical treatment.
Can Acute Appendicitis Be Prevented?
There is no proven method to fully prevent acute appendicitis. Early recognition of symptoms and prompt medical care are the most effective ways to reduce the risk of complications.
When to See a Doctor
Seek medical evaluation promptly for:
- Abdominal pain that worsens or shifts to the lower right side
- Abdominal pain accompanied by nausea, vomiting, or fever
Prompt assessment is important, as early treatment reduces the risk of rupture and serious infection.
Frequently Asked Questions
What is acute appendicitis?
It is a sudden inflammation of the appendix that typically worsens quickly and often requires urgent medical treatment.
Is acute appendicitis serious?
Yes. Without treatment, it can lead to rupture and life-threatening complications.
How is acute appendicitis treated?
The most common treatment is surgical removal of the appendix. In some cases, antibiotics may be used initially, but surgery may still be needed later.
How long does recovery take after an appendectomy?
Recovery time varies. Many people recover within several weeks, depending on the type of surgery and whether complications occurred.
Where is appendix pain usually felt?
Pain often begins near the belly button and later moves to the lower right side of the abdomen.
Can drinking alcohol cause appendicitis?
There is no high-quality evidence supporting this.
Can steroids cause appendicitis?
There is no high-quality evidence supporting this.
Can trauma cause appendicitis?
There is no high-quality evidence supporting this.
APA Reference List
Cleveland Clinic. (2023, May 9). Appendicitis: Signs & symptoms, causes, diagnosis & treatment. https://my.clevelandclinic.org/health/diseases/8095-appendicitis
Johns Hopkins Medicine. (n.d.). Appendicitis. Retrieved January 1, 2026, from https://www.hopkinsmedicine.org/health/conditions-and-diseases/appendicitis
Lotfollahzadeh, S., Lopez, R. A., & Deppen, J. G. (2024). Appendicitis. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK493193/
Mayo Clinic Staff. (2025, January 18). Appendicitis: Symptoms and causes. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/appendicitis/symptoms-causes/syc-20369543
National Health Service (NHS). (2024, August 9). Appendicitis. https://www.nhs.uk/conditions/appendicitis/
National Institute of Diabetes and Digestive and Kidney Diseases. (2021, July). Appendicitis. https://www.niddk.nih.gov/health-information/digestive-diseases/appendicitis
National Institute of Diabetes and Digestive and Kidney Diseases. (2021, July). Symptoms & causes of appendicitis. https://www.niddk.nih.gov/health-information/digestive-diseases/appendicitis/symptoms-causes
National Institute of Diabetes and Digestive and Kidney Diseases. (2021, July). Treatment for appendicitis. https://www.niddk.nih.gov/health-information/digestive-diseases/appendicitis/treatment
U.S. National Library of Medicine. (2025, April 21). Appendicitis (MedlinePlus Medical Encyclopedia). https://medlineplus.gov/ency/article/000256.htm