What is the treatment approach for a patient presenting with food poisoning, considering factors such as age, health status, and potential complications like dehydration or severe symptoms?

Treatment for Food Poisoning

The cornerstone of food poisoning treatment is oral rehydration therapy with reduced osmolarity oral rehydration solution (ORS) for mild to moderate dehydration, with intravenous isotonic fluids reserved for severe dehydration or shock. 1, 2

Initial Assessment

Evaluate the patient's hydration status using clinical signs:

• Mild dehydration (3-5% fluid deficit): Increased thirst, slightly dry mucous membranes 1, 3
• Moderate dehydration (6-9% fluid deficit): Loss of skin turgor, dry mucous membranes, sunken eyes 1, 3
• Severe dehydration (≥10% fluid deficit): Severe lethargy or altered consciousness, prolonged skin fold, hypovolemic shock, requires immediate intervention 1, 3

Check for red flags requiring immediate medical attention: inability to keep down fluids for >24 hours, severe abdominal pain, persistent high fever, frank blood in stool or vomit, confusion, or severe postural dizziness preventing standing. 2

Rehydration Protocol

For Mild to Moderate Dehydration

Administer reduced osmolarity ORS as first-line therapy:

• Mild dehydration: 50 mL/kg over 2-4 hours 1, 3
• Moderate dehydration: 100 mL/kg over 2-4 hours 1, 3
• After each bowel movement: Adults should consume as much ORS as desired; children <2 years get 50-100 mL, older children get 100-200 mL 2, 3

If the patient cannot tolerate oral intake but is not in shock, consider nasogastric tube administration at 15 mL/kg/hour. 1, 2

Reassess hydration status after 3-4 hours and continue treatment according to the degree of dehydration at that time. 1, 2

For Severe Dehydration

This is a medical emergency requiring immediate intravenous therapy:

• Administer Ringer's lactate or normal saline in 20 mL/kg boluses 1, 3
• Continue IV rehydration until pulse, perfusion, and mental status normalize 1, 3
• Once stabilized, the remaining deficit can be replaced using ORS 1, 3

Nutritional Management

Resume age-appropriate diet during or immediately after rehydration is completed. 1, 3 There is no justification for "resting the bowel" through fasting—this delays recovery. 1, 3

• Breast-fed infants: Continue nursing on demand throughout the illness 1, 2
• Bottle-fed infants: Resume full-strength formula immediately upon rehydration 1
• Children >4-6 months and adults: Offer energy-rich, easily digestible foods as soon as appetite returns 1, 3

Antimicrobial Therapy

In most people with acute watery diarrhea without recent international travel, empiric antimicrobial therapy is not recommended. 1 Antibiotics are contraindicated for routine treatment of uncomplicated watery diarrhea. 1

Exceptions where empiric antibiotics may be considered:

• Immunocompromised patients 1, 4
• Elderly patients 4
• Patients with diabetes, liver cirrhosis, or intestinal hypomotility 4
• Ill-appearing young infants 1

Specific indications for antimicrobials include:

• Cholera 1
• Shigella dysentery 1
• Amoebic dysentery 1
• Acute giardiasis 1

Ancillary Medications

Antimotility Agents

Loperamide is contraindicated in children <18 years of age with acute diarrhea. 1, 5 It should be avoided at any age in suspected inflammatory diarrhea, diarrhea with fever, or bloody diarrhea due to risk of toxic megacolon. 1

For immunocompetent adults with acute watery diarrhea, loperamide may be given:

• Initial dose: 4 mg (two capsules) followed by 2 mg after each unformed stool 5
• Maximum daily dose: 16 mg (eight capsules) 5
• Use only after adequate hydration is achieved 1

Antiemetics

Ondansetron may be given to children >4 years of age and adolescents with vomiting to facilitate tolerance of oral rehydration. 1, 2

Probiotics

Probiotic preparations may be offered to reduce symptom severity and duration in immunocompetent adults and children. 1

Critical Pitfalls to Avoid

• Do not use popular beverages like apple juice, Gatorade, or commercial soft drinks for rehydration—they lack appropriate electrolyte composition and can worsen dehydration 3
• Do not administer antidiarrheal drugs, stimulants, steroids, or purgatives—they are contraindicated and can produce adverse effects 1, 3
• Do not delay treatment for severe dehydration—it constitutes a medical emergency 3
• Avoid caffeine, alcohol, fatty or spicy foods during the acute illness 2

Special Populations

Older Adults

For older adults with dehydration who appear well, encourage increased fluid intake with preferred beverages (water, tea, coffee, milk, fruit juices, soups). 1, 2 Coffee does not cause dehydration despite common myths. 1

For those who appear unwell, offer subcutaneous or intravenous fluids in parallel with oral intake. 2 Subcutaneous dextrose infusions can be effective with similar adverse effect rates as IV infusion. 2

Immunocompromised Patients

These patients are at higher risk for severe complications and may require empiric antimicrobial therapy even with watery diarrhea. 1, 4 Maintain close monitoring and lower threshold for hospitalization.