I have three episodes of diarrhea per day with burning abdominal pain, nausea, loss of appetite, and myalgia—what is the appropriate management?

Management of Acute Diarrhea with Systemic Symptoms

You should initiate oral rehydration immediately, perform a thorough clinical and epidemiological evaluation to identify the cause, obtain selective fecal studies if indicated, and consider empiric antibiotic therapy if bacterial dysentery is suspected based on fever and systemic symptoms. 1

Immediate Priority: Rehydration

• Begin oral rehydration therapy as the first-line intervention for all patients with acute diarrhea, regardless of suspected etiology 1
• Assess for signs of dehydration including dizziness, thirst, reduced urine output, and orthostatic vital signs 1
• The combination of diarrhea with nausea and vomiting increases dehydration risk and requires aggressive fluid replacement 1

Critical Clinical Evaluation

Perform a comprehensive assessment focusing on specific epidemiological and clinical features that guide diagnosis and management: 1

• Travel history: Recent travel to developing countries suggests traveler's diarrhea (enterotoxigenic E. coli, Campylobacter, Salmonella, Shigella) 1
• Food exposure: Ingestion of raw/undercooked meat, raw seafood, or unpasteurized milk 1
• Stool characteristics: Frequency (you have 3 episodes/day, meeting the definition of diarrhea), presence of blood, mucus, or black tarry appearance 1
• Fever presence: Up to 30% of infectious diarrhea presents with fever; its presence suggests invasive bacterial infection requiring antibiotics 1
• Systemic symptoms: Your myalgia combined with GI symptoms raises consideration of viral gastroenteritis or, in the current epidemiological context, COVID-19 1

Diagnostic Testing: Selective Approach

Do NOT routinely test all patients with acute diarrhea—reserve testing for specific high-risk scenarios: 1

Indications for fecal studies:

• Profuse watery diarrhea with signs of hypovolemia 1
• Grossly bloody stools 1
• Fever >38.5°C (101.3°F) 1
• Passage of ≥6 unformed stools per 24 hours 1
• Duration >7 days 1
• Immunocompromised state 1
• Elderly patients or those with significant comorbidities 1

Recommended tests when indicated:

• Stool culture for bacterial pathogens (Salmonella, Shigella, Campylobacter) 1
• Stool testing for Clostridioides difficile if recent antibiotic use or healthcare exposure 2
• Complete blood count to assess for leukocytosis suggesting bacterial infection 1
• Consider SARS-CoV-2 testing given the constellation of diarrhea, nausea, loss of appetite, and myalgia 1

Empiric Antibiotic Therapy: When to Treat

Antibiotics should be considered in specific clinical scenarios, not routinely for all acute diarrhea: 1

Strong indications for empiric antibiotics:

• Traveler's diarrhea with moderate-to-severe symptoms: Fluoroquinolones (ciprofloxacin 500mg twice daily for 3 days) or azithromycin 1000mg single dose 1
• Suspected shigellosis (bloody diarrhea with fever and abdominal cramps): Fluoroquinolones or azithromycin 1
• Suspected campylobacter (especially if travel to Asia where quinolone resistance is high): Azithromycin 500mg daily for 3 days 1
• Febrile dysentery (fever with bloody diarrhea): Cephalosporins or fluoroquinolones 1

Important caveat:

• For suspected Campylobacter from Asia, use macrolides (azithromycin) rather than fluoroquinolones due to increasing quinolone resistance 1

Symptomatic Management

Antimotility agents—Critical contraindications:

• AVOID loperamide if you have bloody diarrhea, high fever, or suspected Shiga toxin-producing E. coli 1, 3
• Loperamide can be used cautiously for non-bloody, non-febrile diarrhea in immunocompetent adults 3
• Maximum dose: 16mg/day; discontinue if no improvement in 48 hours 3
• Monitor for cardiac adverse reactions, especially if taking CYP3A4 inhibitors or medications that prolong QT interval 3

Antiemetics:

• Consider ondansetron for severe nausea/vomiting that impairs oral rehydration 1

COVID-19 Consideration

Your symptom constellation—diarrhea, nausea, loss of appetite, and myalgia—is consistent with COVID-19 gastrointestinal presentation: 1

• Diarrhea occurs in 22% of COVID-19 patients, with higher rates (24%) in hospitalized patients 1
• GI symptoms (diarrhea or nausea/vomiting) are associated with 70% increased risk of testing positive for COVID-19 1
• Consider SARS-CoV-2 testing, especially if there are respiratory symptoms or known exposures 1

Red Flags Requiring Urgent Evaluation

Seek immediate medical attention if you develop: 1, 4

• Signs of severe dehydration (inability to maintain oral intake, decreased urine output, altered mental status) 1
• Bloody stools 1, 4
• High fever (>39°C/102.2°F) or persistent fever >48 hours 1
• Severe abdominal pain not relieved by bowel movements 1
• Symptoms lasting >48 hours without improvement 3, 4
• Development of peritoneal signs (rigid abdomen, rebound tenderness) 5, 6

Expected Clinical Course

• Most acute infectious diarrhea is self-limited, resolving within 3-7 days 4, 2
• If symptoms persist beyond 14 days, this becomes "persistent diarrhea" requiring re-evaluation for alternative diagnoses 1
• Functional disorders should only be considered after excluding infectious and inflammatory causes 7

Common Pitfalls to Avoid

• Do not use antimotility agents empirically without first assessing for bloody diarrhea or high fever 1, 3
• Do not assume all acute diarrhea requires antibiotics—most viral gastroenteritis is self-limited and antibiotics are unnecessary 2
• Do not ignore systemic symptoms like myalgia—they may indicate viral infection (including COVID-19) or more severe bacterial infection 1
• Do not delay rehydration while awaiting test results—dehydration management is the cornerstone of therapy regardless of etiology 1, 2