What could be causing right-sided abdominal pain triggered by drinking water, accompanied by nausea, but no symptoms when eating?

Right-Sided Abdominal Pain Triggered by Water Intake with Nausea

This unusual presentation of right-sided abdominal pain specifically triggered by drinking water (but not eating) with accompanying nausea does not fit typical biliary, gastric, or intestinal pathology and warrants urgent evaluation for non-occlusive mesenteric ischemia (NOMI), particularly if you are critically ill, on vasopressors, or have cardiovascular risk factors.

Immediate Diagnostic Considerations

Most Concerning: Non-Occlusive Mesenteric Ischemia (NOMI)

Right-sided abdominal pain associated with fluid intake in the context of critical illness or cardiovascular compromise is highly suggestive of NOMI 1. This condition presents with:

• Right-sided abdominal pain that may be triggered by any intestinal distension, including water intake 1
• Nausea and potential gastrointestinal bleeding 1
• Pain out of proportion to physical examination findings 2
• Often occurs in critically ill patients requiring vasopressor support 1

NOMI should be suspected if you have any of the following risk factors 1:

• Recent cardiopulmonary resuscitation
• Current vasopressor use (norepinephrine, epinephrine, vasopressin, digoxin)
• Acute profound hypovolemia
• Multiorgan dysfunction
• Recent major surgery or trauma

Alternative Functional Explanation

If you are otherwise healthy without the above risk factors, this presentation suggests functional dyspepsia with atypical triggers 1. The specific triggering by water (but not food) indicates:

• Altered gut-brain communication causing visceral hypersensitivity 1, 3
• Paradoxical response to gastric distension from fluid 3
• Possible disordered eating behavior with excessive water intake 4

Urgent Diagnostic Workup

Immediate Laboratory Tests

Order the following tests immediately 2:

• Complete blood count (looking for leukocytosis suggesting ischemia)
• Serum lactate (elevated in mesenteric ischemia)
• C-reactive protein
• Liver and renal function tests
• Serum amylase or lipase (to exclude pancreatitis)
• Serum electrolytes and glucose 2

Imaging Studies

CT abdomen and pelvis with IV contrast is the diagnostic test of choice 1:

• Sensitivity >90% for detecting mesenteric ischemia 1
• Can identify bowel wall thickening, pneumatosis, mesenteric edema, and ascites 1
• In NOMI, shows bowel ischemia with patent mesenteric vessels 1
• Do not delay CT for renal function concerns—the consequences of missed mesenteric ischemia far outweigh contrast nephropathy risk 1

If CT is negative and you are not critically ill, consider ultrasound of the right upper quadrant 1, 5:

• Evaluates for atypical biliary disease, hepatic pathology, or renal causes 1, 5
• Sensitivity of 96% for gallstones but only 88% for acute cholecystitis 1

Immediate Management

If Critically Ill or High-Risk for NOMI

Initiate aggressive fluid resuscitation immediately 1:

• Crystalloid and blood products to enhance visceral perfusion
• Correct electrolyte abnormalities and metabolic acidosis
• Nasogastric decompression 1

Minimize vasopressor use or switch to agents with less mesenteric vasoconstriction 1:

• Prefer dobutamine, low-dose dopamine, or milrinone over norepinephrine/epinephrine 1
• Consider holding digoxin and vasopressin 1

Urgent surgical consultation is mandatory if imaging shows 1:

• Bowel wall thickening with abnormal enhancement
• Pneumatosis or mesenteric venous gas
• Free air suggesting perforation
• Ascites with peritoneal signs

If Otherwise Healthy (Functional Dyspepsia Suspected)

Start empiric treatment while awaiting diagnostic workup 2:

• High-dose proton pump inhibitor: omeprazole 20-40 mg once daily before meals 2
• Antiemetic for nausea: ondansetron 8 mg sublingual every 4-6 hours (obtain baseline ECG first due to QTc prolongation risk) 2

Test for H. pylori with stool or breath test 1:

• If positive, treat with antibiotics 1
• If negative or symptoms persist after treatment, consider functional dyspepsia 1

Red Flags Requiring Urgent Evaluation

Seek immediate emergency care if you develop 2:

• Fever ≥38°C or tachycardia ≥110 bpm (suggests perforation or sepsis)
• Hematemesis or passage of maroon/bright red blood in stool 1
• Severe pain out of proportion to examination 2
• Abdominal rigidity or peritoneal signs 2
• Hypotension or signs of shock 2

Common Pitfalls to Avoid

Do not assume this is simple gastritis or functional dyspepsia without excluding life-threatening causes first 1, 2. The specific triggering by water intake is atypical and warrants thorough investigation.

Do not delay imaging in elderly patients or those with cardiovascular risk factors 1. Mesenteric ischemia has mortality rates of 25% when bowel infarction occurs, and early diagnosis is critical 1.

Do not attribute symptoms to anxiety or water intoxication without checking serum sodium 4. Excessive water intake with disordered eating can cause hyponatremia and abdominal pain 4.

If symptoms persist despite negative workup, consider endoscopy to exclude peptic ulcer disease, gastritis, or duodenitis 1, 2, particularly if you are ≥25 years old or have alarm features (weight loss, anemia, family history of gastric cancer) 1.