What is the appropriate treatment for a patient with symptoms of food poisoning?

Treatment of Food Poisoning

Rehydration is the cornerstone of food poisoning treatment, with oral rehydration sufficient for mild-to-moderate cases and aggressive isotonic fluid resuscitation (10-20 mL/kg boluses of normal saline) required for severe dehydration or shock. 1

Initial Assessment and Fluid Management

The primary therapeutic intervention focuses on restoring fluid and electrolyte balance:

• Initiate oral rehydration therapy immediately for patients with mild-to-moderate symptoms using electrolyte-rich fluids (sports drinks) or oral rehydration solutions 1, 2
• Administer intravenous isotonic fluids (normal saline) in 10-20 mL/kg boluses for patients presenting with severe dehydration, shock, or inability to tolerate oral intake 1
• Monitor for signs of severe dehydration including altered mental status, decreased urine output, and hemodynamic instability 1

Food poisoning typically causes isotonic dehydration with proportional loss of water and electrolytes, making balanced fluid replacement essential 3.

Symptomatic Management

Antiemetic Therapy

• Consider ondansetron for severe vomiting to facilitate oral rehydration and improve patient comfort 1
• Antiemetics should be given prophylactically when vomiting is prominent 4

Antimotility Agents

• Avoid loperamide and other antimotility agents when bloody diarrhea is present or when Shiga toxin-producing E. coli infection is suspected, as these may worsen outcomes 1
• For non-bloody diarrhea without fever, loperamide may be initiated at 4 mg followed by 2 mg every 2-4 hours or after each unformed stool (maximum 16 mg daily) 4

Antimicrobial Therapy

Empirical antibiotics are NOT routinely recommended for uncomplicated food poisoning. 1, 2

However, antimicrobial therapy should be considered in specific circumstances:

• High-risk patients (elderly, immunocompromised, diabetic, cirrhotic, or those with intestinal hypomotility) may benefit from empirical therapy 2
• Shigellosis with bloody diarrhea warrants antimicrobial treatment to reduce severity and duration 4
  • First-line: Ampicillin (500 mg four times daily for 5 days in adults) or TMP-SMX (160 mg TMP/800 mg SMX twice daily for 5 days) 4
  • For resistant strains: Nalidixic acid (55 mg/kg/day in four divided doses) or tetracycline (50 mg/kg/day in four divided doses) 4
• Perform selective fecal studies based on clinical presentation (fever, bloody diarrhea, severe symptoms, immunocompromised status) before initiating antimicrobials 1

When to Seek Emergency Care

Contact Poison Control Center immediately and activate EMS if:

• Symptoms persist beyond 3 days 1
• Bloody diarrhea develops 1
• Signs of severe dehydration appear (altered mental status, oliguria, hemodynamic instability) 1
• Patient is immunocompromised, elderly, or a young child with severe symptoms 2

Critical Pitfalls to Avoid

• Do not delay rehydration while attempting to identify the specific pathogen 1, 2
• Do not use antimotility agents with bloody diarrhea as this may precipitate hemolytic uremic syndrome with STEC infections 1
• Do not routinely prescribe antibiotics for uncomplicated viral or self-limited bacterial gastroenteritis, as this promotes resistance without clinical benefit 1
• Do not administer anything by mouth for suspected toxic ingestions (zinc phosphide, rodenticides) until directed by Poison Control 5, 6

Nutritional Support During Recovery

• Resume oral intake with electrolyte-rich fluids during the recovery phase, which typically lasts 1-2 days 4
• Patients may experience residual nausea or dyspeptic symptoms but generally tolerate moderate liquid volumes 4
• Ensure adequate caloric intake and consider nutritional supplementation if oral intake remains inadequate 4

Prevention and Follow-up

• Advise strict handwashing and hygiene measures to prevent transmission to household contacts 1
• Educate patients on safe food handling practices to prevent recurrence 2
• Schedule follow-up if symptoms persist beyond expected timeframe or if patient belongs to high-risk group 1