Stomach pains (abdominal pains) can range from mild aches to severe and sharp, stabbing pain.
There are many possible causes of stomach pains. The causes of stomach pains can be grouped by the area of the abdomen in which the pain occurs.
Causes of stomach pains in the upper right quadrant of the abdomen include:
- Acute cholangitis
- Acute cholecystitis
- Acute myocardial infarction
- Budd-Chiari syndrome
- Functional dyspepsia
- Gallstones
- Gastritis/gastropathy
- Gastroesophageal reflux disease (GERD)
- Gastroparesis
- Hepatitis
- Liver abscess
- Pancreatitis
- Peptic ulcer disease
- Perihepatitis
- Portal vein thrombosis
- Sphincter of Oddi dysfunction
Causes of stomach pains in the upper left quadrant of the abdomen are often related to the spleen and include:
- Splenic abscess
- Splenic infarction
- Splenic rupture
- Splenomegaly
Causes of stomach pains in the lower abdomen that are felt on just one side include:
- Acute appendicitis
- Diverticulitis
- Kidney stones
- Pyelonephritis
Causes of stomach pains in the lower abdomen that may be felt on one or both sides include:
- Acute urinary retention
- Cystitis
- Infectious colitis
Causes of stomach pains that have nonspecific or variable patterns of pain (called diffuse pain) include:
- Adrenal insufficiency
- Cancer
- Celiac Disease
- Constipation
- Diverticulosis
- Food poisoning
- Inflammatory bowel disease (IBD)
- Crohn’s disease
- Ulcerative colitis
- Intestinal obstruction
- Irritable bowel syndrome (IBS)
- Ketoacidosis
- Lactose intolerance
- Mesenteric ischemia
- Perforation of gastrointestinal tract
- Peritonitis in peritoneal dialysis patients
- Spontaneous bacterial peritonitis
- Viral gastroenteritis
Causes of abdominal pains in females include:
- Ectopic pregnancy
- Endometriosis
- Endometritis
- Fibroids (leiomyomas)
- Ovarian cancer
- Ovarian hyperstimulation
- Ovarian torsion
- Pelvic inflammatory disease
- Pregnancy/pregnancy complications
- Ruptured ovarian cyst
Causes of abdominal pains in postoperative patients include:
- Hematoma/seroma formation and nerve injury
- Postoperative ileus
- Surgical site infections
How Are Stomach Pains Diagnosed?
The cause of stomach pains is diagnosed with a patient history and physical examination, along with tests such as:
- Blood tests
- Complete blood count (CBC) with differential
- Electrolytes, blood urea nitrogen (BUN), creatinine, and glucose
- Calcium
- Aminotransferases, alkaline phosphatase, and bilirubin
- Iron, total iron binding capacity, and ferritin
- Lipase and/or amylase
- Anti-tissue transglutaminase
- Pregnancy testing for women
- Imaging tests
- Computed tomography (CT) scan
- Magnetic resonance imaging (MRI)
- Ultrasound
- Endoscopy
- Endoscopic retrograde cholangiopancreatography
- Other tests
What Is the Treatment for Stomach Pains?
Treatment for stomach pains varies widely and depends upon the cause.
Treatment for stomach pains may involve:
- Dietary changes
- Medications
- Surgery
- Chemotherapy and/or radiation treatments
From 
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