Chronic abdominal pain (CAP) is pain that persists for more than 3 months either continuously or intermittently (1, 2). Recurrent abdominal pain (RAP) refers to at least three episodes of pain occurring over at least three months that affect the patient's ability to perform normal activities (3). Acute abdominal pain is discussed elsewhere.
CAP occurs any time after 5 years of age. In a large cohort study, 11% of children reported RAP at ≥ 1 assessment (3). Approximately 3% of adults, predominantly women, have CAP (4).
Irritable bowel syndrome (IBS) is a common cause of recurrent abdominal pain and altered bowel habits (5). Centrally-mediated abdominal pain syndrome is another subtype of a disorder of gut-brain interaction but is a less common disorder and does not cause altered bowel habits. Nearly all patients with centrally-mediated abdominal pain have had a prior medical evaluation that did not yield a diagnosis after history, physical, and basic testing (6).
General references
1. Treede RD, Rief W, Barke A, et al. Chronic pain as a symptom or a disease: the IASP Classification of Chronic Pain for the International Classification of Diseases (ICD-11). Pain. 2019;160(1):19-27. doi:10.1097/j.pain.0000000000001384
2. Lukic S, Mijac D, Filipovic B, et al. Chronic Abdominal Pain: Gastroenterologist Approach. Dig Dis. 2022;40(2):181-186. doi:10.1159/000516977
3. Sjölund J, Uusijärvi A, Tornkvist NT, et al. Prevalence and Progression of Recurrent Abdominal Pain, From Early Childhood to Adolescence. Clin Gastroenterol Hepatol. 2021;19(5):930-938.e8. doi:10.1016/j.cgh.2020.04.047
4. Ray BM, Kelleran KJ, Kaisler MC, et al. Emergency Department Visit Frequency Among Adults With Chronic Abdominal Pain: Findings From the 2023 US National Health Interview Survey. Acad Emerg Med. 2025;32(11):1168-1188. doi:10.1111/acem.70085
5. Sabo CM, Grad S, Dumitrascu DL. Chronic Abdominal Pain in General Practice. Dig Dis. 2021;39(6):606-614. doi:10.1159/000515433
6. Keefer L, Drossman DA, Guthrie E, et al. Centrally Mediated Disorders of Gastrointestinal Pain. Gastroenterology. Published online February 19, 2016. doi:10.1053/j.gastro.2016.02.034
Pathophysiology
Physiologic causes of chronic abdominal pain (see table ) result from stimuli of visceral receptors (mechanical, chemical, or both). Pain may be localized or referred, depending on innervation and specific organ involvement.
Irritable bowel syndrome and centrally-mediated abdominal pain syndrome cause pain that started at least 6 months prior to diagnosis and symptoms that have been persistent, with frequency at least 1 day per week over the previous 3 months without evidence of physiologic disease. The pathophysiology of these disorders is complex and seems to involve altered intestinal motility, increased visceral nociception, and psychological factors. Visceral hyperalgesia refers to hypersensitivity to normal amounts of intraluminal distention and heightened perception of pain in the presence of normal quantities of intestinal gas; it may result from remodeling of neural pathways in the gut-brain axis.
Etiology
Approximately 10% of patients have an occult physiologic illness (see table ); the remainder have a disorder of gut-brain interaction (1). However, determining whether a particular abnormality (eg, adhesions, ovarian cyst, endometriosis) is the cause of CAP symptoms or an incidental finding can be difficult.
Selected Structural, Inflammatory, and Metabolic Causes of Chronic Abdominal Pain
Cause | Suggestive Findings* | Diagnostic Approach |
|---|---|---|
Genitourinary disorders | ||
Recurrent UTIs | IVU Ultrasound | |
Discomfort before or during menses | Laparoscopy | |
Vague lower abdominal discomfort, bloating Sometimes a palpable pelvic mass | Pelvic ultrasound Gynecologic consultation | |
Fever, flank pain, dark or bloody urine | Urine culture IVU CT | |
Sequelae of acute PID | Pelvic discomfort History of acute PID | Pelvic examination Sometimes laparoscopy |
Gastrointestinal disorders | ||
In children, failure to thrive Abdominal bloating, diarrhea, and often steatorrhea Symptoms that worsen when gluten-containing products are ingested | Serologic markers, HLA-DQ2/HLA-DQ8 haplotype testing Small-bowel biopsy | |
Several previous discrete episodes of RLQ pain | Abdominal CT Ultrasound | |
Recurrent colicky RUQ pain | Ultrasound | |
Episodes of severe epigastric pain Sometimes malabsorption (eg, diarrhea, fatty stool) Usually a history of acute pancreatitis | Serum lipase levels (frequently not elevated) CT or MRI often with MRCP Stool tests (fecal elastase or fecal fat) | |
Discomfort uncommon but possibly colicky discomfort if left colon is partially obstructed Often occult or visible blood in stool | Colonoscopy | |
Episodic severe pain with fever, anorexia, weight loss, diarrhea Extraintestinal symptoms (joints, eyes, mouth, skin) | CT enterography or upper GI series with SBFT Colonoscopy and esophagogastroduodenoscopy with biopsies | |
Dyspepsia or mild pain Often occult blood in stool | Upper endoscopy | |
Granulomatous enterocolitis | Family history Recurrent infections in other sites (eg, lungs, lymph nodes) | ESR, CRP Colonoscopy CT enterography |
Hiatus hernia with gastroesophageal reflux | Heartburn Sometimes cough and/or hoarseness Symptoms relieved by taking antacids Sometimes regurgitation of gastric contents into the mouth | Barium swallow Endoscopy |
Chronic nonspecific pain Sometimes palpable RLQ mass Fever, diarrhea, weight loss | Tuberculin skin test or interferon-gamma release assays (eg, QuantiFERON-TB Gold test, T-SPOT.TB test) Endoscopy for biopsy CT with oral contrast Chest radiograph | |
Bloating and cramps after ingesting milk products | Hydrogen breath test Trial of elimination of lactose-containing foods | |
Other food intolerance (eg, fructose intolerance, sucrose-isomaltase deficiency) FODMAPs | Abdominal pain and cramping Bloating and distention Nausea and diarrhea | Disaccharidase test Breath test for fructose intolerance Sucrose-isomaltose deficiency testing Elimination diet |
Severe upper abdominal pain that
May cause obstructive jaundice | CT MRI/MRCP or ERCP Endoscopic ultrasound | |
Parasitic infestation (particularly giardiasis) | History of travel or exposure Cramps, flatulence, diarrhea | Stool examination for ova or parasites Stool enzyme immunoassay (for Giardia) |
Upper abdominal pain relieved by food and antacids May awaken patient at night | Endoscopy and biopsy for Helicobacter pylori H. pylori breath test or stool antigen assays Evaluation of nonsteroidal anti-inflammatory drug, alcohol, and tobacco use Stool examination for occult blood | |
Postoperative adhesive bands | Previous abdominal surgery Colicky discomfort accompanied by nausea and sometimes vomiting | Upper GI series, SBFT, or CT enterography Abdominal CT |
Crampy pain with bloody diarrhea | Sigmoidoscopy Rectal biopsy Colonoscopy Sometimes fecal calprotectin | |
Systemic disorders | ||
Abdominal epilepsy | Very rare Episodic pain No other GI symptoms | EEG |
Recurrent severe abdominal pain, vomiting Benign abdominal examination Sometimes neurologic symptoms (eg, muscle weakness, seizures, mental disturbance) In some types, skin lesions | Urine porphobilinogen and delta-aminolevulinic acid screeningUrine porphobilinogen and delta-aminolevulinic acid screening RBC deaminase assay | |
Cannabis use (including cannabinoid hyperemesis syndrome) | Persistent nausea, vomiting, and dyspepsia, often relieved with a hot shower or marijuana cessation Usually requires chronic use of cannabis | History and physical examination Urine drug screen |
Family history Quotidian fever and peritonitis often accompanying the bouts of pain Starting in childhood or adolescence | Genetic testing | |
Symptoms developing only after consuming certain foods (eg, seafood) | Elimination diet | |
Immunoglobulin A–associated vasculitis (formerly Henoch-Schönlein purpura) | Palpable purpuric rash Joint pains Occult blood in stool | Biopsy of skin lesions |
Family history Pain often with peripheral angioedema and fever | Serum complement level (C4) during attacks | |
Cognitive/behavioral abnormalities | Blood lead level | |
Rare variant with epigastric pain and vomiting Mainly in children Usually family history of migraine | History and physical examination | |
Family history Severe episodes of abdominal pain lasting over a day Recurrent pain in nonabdominal sites | Sickle preparation Hemoglobin electrophoresis | |
* Findings are not always present and may be present in other disorders. | ||
CRP = C-reactive protein; EEG = electroencephalography; ERCP = endoscopic retrograde cholangiopancreatography; ESR = erythrocyte sedimentation rate; FODMAP = fermentable oligosaccharides, disaccharides, monosaccharides, and polyols; GI = gastrointestinal; IVU = intravenous urography; MRCP = magnetic resonance cholangiopancreatography; PID = pelvic inflammatory disease; RBC = red blood cell; RLQ = right lower quadrant; RUQ = right upper quadrant; SBFT = small-bowel follow-through; TB = tuberculosis; UTI = urinary tract infection. | ||
Modified from Barbero GJ. Recurrent abdominal pain in childhood. Pediatr Rev. 1982;4(1):29–34. doi: 10.1542/pir.4-1-29, and from Greenberger NJ. Sorting through nonsurgical causes of acute abdominal pain. J Crit Illn. 7:1602–1609, 1992. | ||
Etiology reference
1. Eikelboom EM, Tak LM, Roest AM, Rosmalen JGM. A systematic review and meta-analysis of the percentage of revised diagnoses in functional somatic symptoms. J Psychosom Res. 2016;88:60-67. doi:10.1016/j.jpsychores.2016.07.001
Evaluation
History
History of present illness should elicit pain location, quality, duration, timing and frequency of recurrence, and factors that worsen or relieve pain (particularly eating or moving bowels).
A dietary history is important. A specific inquiry as to whether milk and milk products cause abdominal cramps, bloating, or distention is needed because lactose intolerance is common, especially among people of African, Hispanic, Asian (particularly East Asian countries), and American Indian heritage, with increasing frequency with aging. Other food triggers may also be identified as being temporally related to bloating or ingestion such as the ingestion of large amounts of carbonated beverages, fruit juices (which may contain significant quantities of fructose and sorbitol), or gas-producing foods (eg, beans, onions, cabbage, cauliflower).
Review of systems should assess for concomitant GI symptoms such as gastroesophageal reflux, anorexia, bloating or “gas,” nausea, vomiting, jaundice, melena, hematuria, hematemesis, weight loss, and mucus or blood in the stool. Bowel symptoms, such as diarrhea, constipation, and changes in stool consistency, color, or elimination pattern, are particularly important.
Past medical history should include nature and timing of any abdominal surgery and the results of previous tests that have been performed and treatments that have been tried. A medication/drug history should include details concerning prescription and illicit drug use as well as alcohol.
Family history of recurrent abdominal pain (RAP), fevers, or both should be ascertained, as well as known diagnoses of sickle cell trait or disease, familial Mediterranean fever, and porphyria.
Physical examination
Review of vital signs should particularly note presence of fever or tachycardia.
General examination should seek presence of jaundice, rash, and peripheral edema.
Abdominal examination should note areas of tenderness, presence of peritoneal findings (eg, guarding, rigidity, rebound), and any masses or organomegaly. Evaluation for abdominal wall pain (Carnett sign) can help distinguish between somatic and visceral pain (1).
Rectal examination and (in women) pelvic examination to locate tenderness and masses and stool examination for occult blood are essential.
Red flags
The following findings are of particular concern:
Fever
Anorexia, weight loss
Pain that awakens patient
Blood in vomit, stool, or urine
Severe or frequent vomiting
Jaundice
Edema
Abdominal mass or organomegaly
Interpretation of findings
History and physical examination alone infrequently provides a firm diagnosis.
Identifying whether chronic abdominal pain (CAP) is due a disorder of gut-brain interaction can be difficult. Although the presence of red flag findings indicates a high likelihood of a structural, inflammatory, or metabolic cause, their absence does not rule it out. Pain that wakes the patient is usually not due to a disorder of the gut-brain axis. Some findings suggestive of specific disorders are listed in table . Psychosocial factors, including anxiety, depression, and significant life stressors, are commonly associated with disorders of gut-brain interaction. The gut-brain axis operates bidirectionally—chronic pain and altered bowel function can precipitate psychological distress, just as anxiety and stress can influence pain perception and gastrointestinal motility.
The Rome IV criteria are consensus guidelines that provide a framework for diagnosing disorders of the gut-brain interaction, including irritable bowel syndrome (2). According to these criteria, irritable bowel syndrome is defined as the presence of abdominal pain for at least 1 day/week in the last 3 months along with at least 2 of the following:
Pain is related to defecation.
Pain is associated with a change in frequency of defecation.
Pain is associated with a change in consistency of stool.
Testing
In general, simple tests (including urinalysis, complete blood count, liver tests, blood urea nitrogen, glucose, and lipase) should be performed. Abnormalities in these tests, the presence of concerning findings, or specific clinical findings mandate further testing, even if previous assessments have been negative. Specific tests depend on the findings (see ). For example, imaging may include ultrasound to exclude ovarian cancer in women > 50 years, CT of the abdomen and pelvis with contrast, upper GI endoscopy (particularly in patients > 60 years old) or colonoscopy, and perhaps small-bowel imaging or stool testing.
The benefits of testing patients with no red flag findings are unclear. Patients > 45 or with risk factors for colon cancer (eg, family history) should undergo colonoscopy if not previously screened; patients ≤ 45 can be observed or have CT of the abdomen and pelvis with contrast if an imaging study is desired. Magnetic resonance cholangiopancreatography (MRCP), endoscopic retrograde cholangiopancreatography (ERCP), and laparoscopy are rarely helpful in the absence of specific indications (eg, concern for pancreatitis, ascending cholangitis, or abnormal laboratory tests suggestive of hepatobiliary or pancreatic disease).
Between the initial evaluation and the follow-up visit, the patient (or family, if the patient is a child) should record any pain, including its nature, intensity, duration, and precipitating factors. Diet, defecation pattern, and any remedies tried (and the results obtained) should also be recorded. This record may reveal inappropriate behavior patterns and exaggerated responses to pain or otherwise suggest a diagnosis.
Evaluation references
1. Sun XX, Liu H, Qin XZ, et al. The Diagnostic Value of Carnett's Test with Chronic Abdominal Pain: A Narrative Review. Curr Pain Headache Rep. 2024;28(4):251-257. doi:10.1007/s11916-024-01223-9
2. Drossman DA. Functional gastrointestinal disorders: History, pathophysiology, clinical features, and Rome IV. Gastroenterology. 2016;150:1262–1279. doi: 10.1053/j.gastro.2016.02.032
Treatment
Specific conditions are treated.
If the diagnosis of a disorder of gut-brain interaction is made, frequent examinations and tests are typically not needed unless there are new or changing clinical features or alarming symptoms.
There are no modalities to cure disorders of gut-brain interaction; however, many helpful measures are available with the goal of improving function and quality of life (1). These measures rest on a foundation of a trusting, empathic relationship between the physician, patient, and family. Patients should be reassured that they are not in danger; specific concerns should be sought and addressed. The physician should explain the laboratory findings and the nature of the problem and describe how the pain is generated and how the patient perceives it (ie, there may be a tendency to feel pain at times of stress). It is important to avoid perpetuating the negative psychosocial consequences of chronic pain (eg, prolonged absences from school or work, withdrawal from social activities) and to promote independence, social participation, and self-reliance. These strategies help the patient control or tolerate the symptoms while participating fully in everyday activities.
Agents such as antispasmotics, peppermint oil, and tricyclic antidepressants can be effective (2). Opioids should be avoided because of the concern about potential dependency and possibility of narcotic bowel syndrome (3).
Dietary modification and consumption of high-fiber foods or fiber supplements may help some patients with IBS. Evidence supporting the use of probiotics for centrally mediated abdominal pain syndrome is currently limited.
Cognitive methods (eg, cognitive-behavioral therapy, relaxation training, biofeedback, hypnosis) may directly reduce abdominal pain and gastrointestinal symptoms by modulating pain perception, visceral hypersensitivity, and gut motility through brain-gut axis mechanisms (2). Regular follow-up visits should be scheduled weekly, monthly, or bimonthly, depending on the patient’s needs, and should continue until well after the problem has resolved. Psychiatric referral may be required if symptoms persist, especially if the patient has depression or there are significant psychological stressors at home.
Treatment references
1. Tome J, Kamboj AK, Loftus CG. Approach to Disorders of Gut-Brain Interaction. Mayo Clin Proc. 2023;98(3):458-467. doi:10.1016/j.mayocp.2022.11.001
2. Goodoory VC, Khasawneh M, Thakur ER, et al. Effect of Brain-Gut Behavioral Treatments on Abdominal Pain in Irritable Bowel Syndrome: Systematic Review and Network Meta-Analysis. Gastroenterology. 2024;167(5):934-943.e5. doi:10.1053/j.gastro.2024.05.010
3. Keefer L, Ko CW, Ford AC. AGA Clinical Practice Update on Management of Chronic Gastrointestinal Pain in Disorders of Gut-Brain Interaction: Expert Review. Clin Gastroenterol Hepatol. 2021;19(12):2481-2488.e1. doi:10.1016/j.cgh.2021.07.006
Key Points
Most cases of chronic abdominal pain represent a disorder of gut-brain interaction.
Red flag findings indicate a possible structural, inflammatory, or metabolic cause and the need for further assessment.
Testing is guided by clinical features.
Repeated testing after structural, inflammatory, or metabolic causes are ruled out is usually not necessary.
