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Acute Abdominal Pain


Norton J. Greenberger

, MD, Brigham and Women's Hospital

Last full review/revision May 2018 by Norton J. Greenberger, MD

Abdominal pain is common and often minor. Severe abdominal pain that comes on quickly, however, almost always indicates a significant problem. The pain may be the only sign of the need for surgery and must be attended to swiftly. Abdominal pain is of particular concern in people who are very young or very old and those who have human immunodeficiency virus (HIV) infection or are taking drugs that suppress the immune system. Older adults may have less abdominal pain than younger adults with a similar disorder, and, even if the condition is serious, the pain may develop more gradually. Abdominal pain also affects children, including newborns and infants—who cannot communicate the reason for their distress.

Types of Abdominal Pain

There are different types of abdominal pain depending on the structures involved.

Visceral pain comes from the organs within the abdominal cavity (which are called the viscera). The viscera's nerves do not respond to cutting, tearing, or inflammation. Instead, the nerves respond to the organ being stretched (as when the intestine is expanded by gas) or surrounding muscles contract. Visceral pain is typically vague, dull, and nauseating. It is hard to pinpoint. Upper abdominal pain results from disorders in organs such as the stomach, duodenum, liver, and pancreas. Midabdominal pain (near the navel) results from disorders of structures such as the small intestine, upper part of the colon, and appendix. Lower abdominal pain results from disorders of the lower part of the colon and organs in the genitourinary tract.

Somatic pain comes from the membrane (peritoneum) that lines the abdominal cavity (peritoneal cavity). Unlike nerves in the visceral organs, nerves in the peritoneum respond to cutting and irritation (such as from blood, infection, chemicals, or inflammation). Somatic pain is sharp and fairly easy to pinpoint.

Referred pain is pain perceived distant from its source (see Figure: What Is Referred Pain?). Examples of referred pain are groin pain caused by kidney stones and shoulder pain caused by blood or infection irritating the diaphragm.

What Is Referred Pain?

Pain felt in one area of the body does not always represent where the problem is because the pain may be referred there from another area. For example, pain produced by a heart attack may feel as if it is coming from the arm because sensory information from the heart and the arm converge on the same nerve pathways in the spinal cord.

What Is Referred Pain?


Peritonitis is inflammation of the peritoneal cavity. It is very painful and almost always signals a very serious or life-threatening disorder. It can result from any abdominal problem in which the organs are inflamed or infected. Common examples include appendicitis, diverticulitis, and pancreatitis. Also, blood and body fluids (such as intestinal contents or urine) are very irritating when they leak into the peritoneal cavity and can cause peritonitis. Disorders that cause blood and body fluids to leak include spontaneous organ rupture (such as a perforated intestine or ruptured ectopic pregnancy) and severe abdominal injury. People who have fluid in the peritoneal cavity (the fluid is called ascites) are at risk of developing an infection. Such an infection is called spontaneous bacterial peritonitis.

Once peritonitis has been present for a number of hours, the inflammation causes fluid to leak into the abdominal cavity. The person may then develop dehydration and go into shock. Inflammatory substances released into the bloodstream may affect various organs, causing severe lung inflammation, kidney failure, liver failure, and other problems. Without treatment, people may die.


Pain can arise from any of many causes, including infection, inflammation, ulcers, perforation or rupture of organs, muscle contractions that are uncoordinated or blocked by an obstruction, and blockage of blood flow to organs.

Immediately life-threatening disorders, which require rapid diagnosis and surgery, include

  • Ruptured abdominal aortic aneurysm
  • Perforated stomach or intestine
  • Blockage of blood flow to the intestine (mesenteric ischemia)
  • Ruptured ectopic pregnancy

Serious disorders that are nearly as urgent include

Sometimes, disorders outside the abdomen cause abdominal pain. Examples include heart attack, pneumonia, and twisting of a testis (testicular torsion). Less common problems outside the abdomen that cause abdominal pain include diabetic ketoacidosis, porphyria, sickle cell disease, and certain bites and poisons (such as a black widow spider bite, heavy metal or methanol poisoning, and some scorpion stings).

Abdominal pain in newborns, infants, and young children has numerous causes not encountered in adults (see Table: Abdominal Pain in Newborns, Infants, and Young Children).

Abdominal Pain in Newborns, Infants, and Young Children

Cause of Pain



Meconium peritonitis

Inflammation and sometimes infection of the abdominal cavity and its lining (peritonitis) caused by a perforation in the intestine and leakage of meconium (the dark green fecal material that is produced in the intestines before birth)

Occurs while infants are still in the womb or shortly after birth

Hypertrophic pyloric stenosis

A blockage at the stomach outlet (duodenum)

Forceful (projectile) vomiting occurs after feedings

Usually begins between birth and 4 months of age

Esophageal webs

Thin membranes that grow across the inside of the upper one third of the esophagus from its lining (mucosa)

Solids are difficult to swallow


Twisting of a loop of the intestines

Causes intestinal obstruction and cuts off the blood supply to intestines

Commonly, vomiting, diarrhea, abdominal swelling, and episodic and excessive crying (colic)

Imperforate anus (anal atresia)

Narrowing or blockage of the anal opening

Normally detected by doctors when infants are examined after birth and usually requires immediate surgery


The condensing and overlapping (telescoping) of one portion of the intestine into another

Causes intestinal obstruction and cuts off the blood supply to the intestine

Causes sudden pain, vomiting, bloody stools, and fever

Typically affects children between the ages of 6 months and 2 years

Intestinal obstruction

A blockage that completely stops or seriously impairs the passage of intestinal contents

Commonly caused by a birth defect, meconium, or volvulus in newborns and infants

Various symptoms depending on the type of obstruction but may include cramping pain in the abdomen, bloating, disinterest in eating, vomiting, severe constipation, diarrhea, and fever


The following information can help people decide when a doctor's evaluation is needed and help them know what to expect during the evaluation.

Warning signs

In people with acute abdominal pain, certain symptoms and characteristics are cause for concern. They include

  • Severe pain
  • Signs of shock (for example, a rapid heart rate, low blood pressure, sweating, and confusion)
  • Signs of peritonitis (for example, constant pain that doubles the person over and/or pain that worsens with gentle touching or with bumping the bed)
  • Swelling of the abdomen

When to see a doctor

People who have warning signs should go to the hospital right away. People who have no warning signs should see a doctor within a day.

What the doctor does

Doctors ask questions about the person's symptoms and medical history and do a physical examination. What doctors find during the history and physical examination helps them decide what, if any, tests need to be done. Doctors follow the same process whether they are evaluating mild or severe pain, although a surgeon may be involved early on in the evaluation of severe abdominal pain.

When taking the medical history (see Table: History in People With Acute Abdominal Pain), doctors ask questions about the pain's location (see Figure: Causes of Abdominal Pain by Location) and characteristics, whether the person has had similar symptoms in the past, and what other symptoms the person has along with the abdominal pain. Symptoms such as heartburn, nausea, vomiting, diarrhea, constipation, jaundice, blood in the stool or urine, coughing up blood, and weight loss help guide the doctor's evaluation. Doctors ask questions about drugs taken, including prescription and illicit drugs as well as alcohol.

Doctors ask questions about known medical conditions and previous abdominal surgeries. Women are asked whether they are or could be pregnant.

When conducting a physical examination, doctors first note the person's general appearance. A comfortable-appearing person rarely has a serious problem, unlike one who is anxious, pale, sweating, or in obvious pain. The focus of the examination is the abdomen, and doctors inspect, tap, and touch (a process called palpation) the abdominal area. They usually examine the rectum and pelvis (for women) to locate tenderness, masses, and blood.

Doctors touch the whole abdomen gently to detect areas of particular tenderness, as well as the presence of guarding, rigidity, rebound, and any masses. Guarding is when a person involuntarily contracts the abdominal muscles when the doctor touches the abdomen. Rigidity is when the abdominal muscles stay firmly contracted even when the doctor is not touching them. Rebound is when a person flinches in pain as the doctor's hand is briskly withdrawn. Guarding, rigidity, and rebound are signs of peritonitis.

History in People With Acute Abdominal Pain

Questions That Doctors Ask

Possible Responses

Possible Causes or Source

Where is the pain?

See Causes of Abdominal Pain by Location

See Causes of Abdominal Pain by Location

What is the pain like?

Waves of sharp pain that “take the breath away”

Renal or biliary colic (episodes of intense pain in the kidneys or gallbladder)

Waves of dull pain with vomiting

Intestinal obstruction

Colicky pain that becomes steady


Strangulating intestinal obstruction (blockage that cuts off the blood supply to the intestines)

Mesenteric ischemia (blockage of blood flow to part of the intestines due to a blood clot or buildup of fatty materials in an artery)

Sharp, constant pain, worsened by movement


Tearing pain

Aortic dissection (a tear in the inner layer of the aorta)

Dull ache



Kidney infection

Have you had it before?


Recurring problems such as ulcer disease, gallstones, diverticulitis, or mittelschmerz (pain during ovulation, usually the middle of the menstrual cycle)

Did the pain begin suddenly?

Sudden ("like a light switching on”)

Perforated ulcer

Kidney stone

Ruptured ectopic (abnormally located) pregnancy

Twisting of ovary or testicular torsion

Some ruptured aneurysms

Less sudden

Most other causes

How severe is the pain?

Severe pain

A tear (perforation) in an organ

Kidney stone



Severe pain but a comparatively normal physical examination

Mesenteric ischemia

Does the pain travel to any other part of your body?

Right shoulder blade

Gallbladder pain

Left shoulder region

Ruptured spleen


Pubic bone or vagina

Kidney pain


Ruptured aortic aneurysm


Sometimes perforated ulcer

What relieves the pain?


Peptic ulcer disease

Lying as quietly as possible


What other symptoms occur with the pain?

Vomiting that precedes the pain and is followed by diarrhea


Delayed vomiting, no bowel movements, and no passing of gas (flatulence)

Sudden (acute) intestinal obstruction

Severe vomiting that precedes intense pain in the upper middle of the abdomen, left chest, or shoulder

Perforation of the esophagus

Causes of Abdominal Pain by Location

Causes of Abdominal Pain by Location


Sometimes, people have findings so significant that doctors realize right away that they need surgery. Doctors try not to delay surgery on such people by doing tests. However, more often, doctors must do tests to help choose among several different causes suggested by the person's symptoms and physical examination results. Doctors select tests based on what they suspect.

  • Urine pregnancy test for all girls and women of childbearing age
  • Imaging tests based on suspected diagnosis

An abdominal computed tomography (CT) scan helps identify many, but not all, causes of abdominal pain. Urine tests (for example, urinalysis) are frequently done to look for signs of a urinary tract infection or a kidney stone. Blood tests are often done but rarely identify a specific cause (although blood tests can be used to diagnose pancreatitis). An ultrasound is helpful if doctors suspect a gynecologic disorder.


The specific cause of the pain is treated. Until recently, doctors thought that it was not wise to give pain relievers to people with severe abdominal pain until a diagnosis was made because the pain reliever might mask important symptoms. However, pain relievers are now often given while tests are in progress.

Key Points

  • Doctors look first for any life-threatening causes for the pain.
  • Doctors rule out pregnancy in girls and women of childbearing age.
  • Blood tests rarely identify a specific cause of acute abdominal pain.

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