Complaint · Vomiting / diarrhea (adult)

Vomiting & diarrhea: documentation that holds up

Evidence-based · cited·Reviewed Jun 2026

"Gastroenteritis" is the most over-applied label in the ED, and the diagnoses it hides — an inferior MI, DKA, a bowel obstruction, a surgical abdomen, a CNS catastrophe — are the ones that kill. The defensible chart shows the dangerous mimics were considered before the benign label, and documents a successful PO trial before discharge.

01What's at stake

Vomiting and diarrhea are final common pathways for far more than viral gastroenteritis. Inferior MI presents as epigastric pain and vomiting; DKA as nausea and abdominal pain; small-bowel obstruction and appendicitis early on look like a "stomach bug"; and raised intracranial pressure causes vomiting. True gastroenteritis is a diagnosis of exclusion that requires diarrhea — vomiting alone is not gastroenteritis.

02Can't-miss diagnoses

  • ACS (inferior/posterior) — epigastric pain, nausea, vomiting, diaphoresis → ECG. → ECG
  • DKA / metabolic — nausea, vomiting, abdominal pain; check glucose/ketones/anion gap.
  • Bowel obstruction / surgical abdomen — appendicitis, cholecystitis, pancreatitis, mesenteric ischemia, AAA; focal exam, bilious/feculent vomiting, distension.
  • CNS cause — raised ICP, posterior-fossa stroke, meningitis (vomiting with headache/neuro signs).
  • Invasive/inflammatory diarrhea — bloody/febrile diarrhea, recent antibiotics (C. difficile), immunocompromise → stool workup. → stool studies
  • Cannabinoid hyperemesis, toxins, and the dehydrated/hypovolemic elderly.

03History & exam

  • Pain out of proportion or focal, bilious/bloody vomiting, melena/hematochezia, fever, headache/neuro symptoms, cardiac risk, diabetes, recent antibiotics, travel, immunosuppression.
  • ECG for epigastric pain/vomiting with risk; glucose for the diabetic.
  • Abdominal exam (peritonitis, distension, hernias), volume status, and a rectal exam when GI bleeding is suspected.
  • Stool workup for invasive/inflammatory diarrhea (blood, fever, immunocompromise, antibiotics).

Skip the typing

Work the case in the Vomiting / Diarrhea Workup — it records the ECG for epigastric presentations, the stool workup for invasive diarrhea, and the PO trial, and assembles an MDM that documents the dangerous mimics were excluded.

04Management

  • Rehydrate — oral rehydration when tolerated; IV fluids for dehydration; antiemetics and analgesia.
  • PO trial before discharge — document that the patient kept fluids down. → PO trial
  • Antibiotics are not routine for acute infectious diarrhea — reserve for dysentery, severe/septic illness, or specific pathogens; avoid antimotility agents in bloody/inflammatory diarrhea.
  • Treat the cause for any identified mimic; admit the unable-to-tolerate-PO, the significantly dehydrated, and the dangerous diagnosis.

05What to document

▼ weak
"Nausea, vomiting, some diarrhea. Gastroenteritis. Zofran, fluids, discharged."
▲ defensible
"Vomiting and watery (non-bloody) diarrhea ×1 day, multiple sick contacts. No chest/epigastric pain, ECG done (no ischemia); not diabetic, glucose normal (no DKA). Abdomen soft, non-focal, no distension/peritonitis (no surgical abdomen/obstruction); no headache or neuro deficit (no CNS cause). Non-bloody, afebrile, no recent antibiotics or immunocompromise — stool studies not indicated. IV fluids, antiemetic; tolerated oral fluids on a PO trial. Viral gastroenteritis; return precautions for bloody stools, severe/localized pain, inability to keep fluids down, chest pain, or confusion."

06Where charts fail

  • Labeling "gastroenteritis" without diarrhea (vomiting alone) — missing ACS, DKA, obstruction, or a CNS cause.
  • No ECG in an older or at-risk patient with epigastric pain and vomiting.
  • Missing the surgical abdomen behind early "gastro."
  • No documented PO trial before discharge.
  • Giving antimotility agents in bloody/inflammatory diarrhea, or missing C. difficile after antibiotics.

07Sources

  • Shane AL, Mody RK, Crump JA, et al. IDSA clinical practice guidelines for the diagnosis and management of infectious diarrhea. Clin Infect Dis. 2017;65(12):e45-e80.
  • Riddle MS, DuPont HL, Connor BA. ACG clinical guideline: diagnosis, treatment, and prevention of acute diarrheal infections in adults. Am J Gastroenterol. 2016;111(5):602-622.
  • DeVon HA, Burke LA, Vuckovic KM, et al. Symptoms suggestive of acute coronary syndrome — atypical presentations. J Am Heart Assoc. 2017.
  • Hayes BD, Klein-Schwartz W, Doyon S. Toxicity of antidiarrheals and antiemetics. Emerg Med Clin North Am. 2007.

© 2026 Kim Trinh, MD. All rights reserved. Educational only — synthesized from primary literature and guidelines. Synthetic examples. Not medical advice — apply local protocol and judgment.

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