What is the treatment for a 40-year-old male presenting with diarrhea, abdominal pain, and fatigue?

Treatment for Diarrhea in a 40-Year-Old Male with Abdominal Pain and Fatigue

Loperamide is the first-line treatment for this patient with acute diarrhea, starting with an initial dose of 4 mg followed by 2 mg after each loose stool (not exceeding 16 mg/day). 1

Initial Assessment and Management

• Rule out warning signs that would require immediate medical attention: high fever (>38.5°C), blood in stool, severe vomiting, or signs of dehydration 1
• Maintain adequate fluid intake as indicated by thirst, using drinks containing glucose (such as lemonades, sweet sodas, fruit juices) or electrolyte-rich soups 1
• Small, light meals are recommended, guided by appetite 1
• Avoid fatty, heavy, spicy foods, caffeine, and lactose-containing foods which may worsen symptoms 1

Pharmacological Management

First-line Treatment:

• Loperamide 4 mg initially, followed by 2 mg after each loose stool (maximum 16 mg/day) 1
• Loperamide slows small and large intestinal transit, reducing stool frequency and urgency 1
• Many patients learn to use loperamide prophylactically when diarrhea is likely to be problematic 1

Alternative Antidiarrheals:

• Codeine 15-30 mg, 1-3 times daily is effective but more likely to cause sedation and dependency 1

For Abdominal Pain:

• Antispasmodics may be beneficial for pain relief 1
• Those with anticholinergic action (such as dicyclomine, hyoscine) appear slightly more effective but may cause dry mouth 1
• Other antispasmodics like mebeverine and alverine citrate have a more direct inhibitory effect on intestinal smooth muscle 1

If Symptoms Persist

After 24-48 Hours:

• If diarrhea persists for more than 48 hours, seek medical advice 1
• Consider evaluation for potential causes including irritable bowel syndrome (IBS), infection, or other gastrointestinal disorders 1

Second-line Options:

• If IBS is suspected, tricyclic antidepressants (TCAs) may be beneficial for pain management 1
• Start with low doses (e.g., amitriptyline 10 mg once daily) and titrate slowly to 30-50 mg once daily 1
• TCAs normalize rapid small bowel transit in diarrhea-predominant IBS but should be avoided if constipation is a major feature 1

Special Considerations

• About 10% of diarrhea-predominant IBS patients show evidence of bile salt malabsorption and may respond to cholestyramine 1
• If symptoms worsen (severe vomiting, dehydration, persistent fever, abdominal distension, blood in stool), immediate medical attention is required 1
• For persistent symptoms, consider probiotics which may be effective for global symptoms and abdominal pain in IBS 1

Lifestyle Modifications

• Regular exercise is recommended for all patients with IBS 1
• First-line dietary advice should include soluble fiber (e.g., ispaghula), starting at low doses (3-4 g/day) and gradually increasing 1
• Hand hygiene is essential, especially after using the toilet and before preparing or eating food 1

When to Seek Further Medical Evaluation

• If no improvement is seen within 48 hours 1
• If symptoms worsen or overall condition deteriorates 1
• If warning signs develop (severe vomiting, dehydration, persistent fever, abdominal distension, blood in stool) 1
• If fatigue persists despite resolution of diarrhea, further investigation may be warranted 2