1. Clinical Overview
A fixed-dose combination (FDC) drug used for the management of acute infectious diarrhea. Racecadotril is an enkephalinase inhibitor with antisecretory action, reducing fluid and electrolyte loss. Ofloxacin is a second-generation fluoroquinolone antibiotic with broad-spectrum activity against common enteric pathogens. This combination addresses both the symptom (watery diarrhea) and the underlying bacterial cause, providing a comprehensive approach to acute diarrheal illness in the Indian context, where bacterial gastroenteritis is prevalent.
| Onset | Duration | Bioavailability |
|---|---|---|
| Racecadotril: 30-60 minutes for antisecretory effect. Ofloxacin: Systemic absorption begins within 1-2 hours, but clinical improvement in diarrhea may take 24-48 hours. | Racecadotril: Approximately 8 hours per dose. Ofloxacin: Dosing interval is 12 hours, with antibacterial effects persisting beyond its half-life due to concentration-dependent killing. | Racecadotril: Rapidly hydrolyzed to its active metabolite, thiorphan, with bioavailability >90%. Ofloxacin: Oral bioavailability is approximately 95-98%. |
2. Mechanism of Action
Racecadotril acts as a prodrug, converted to thiorphan, which inhibits membrane-bound enkephalinase in the intestinal epithelium. This inhibition increases local concentrations of endogenous enkephalins, which stimulate delta-opioid receptors. This activation reduces intracellular cyclic AMP and inhibits the hypersecretion of water and electrolytes into the gut lumen, without affecting intestinal motility. Ofloxacin inhibits bacterial DNA gyrase (topoisomerase II) and topoisomerase IV, enzymes critical for DNA replication, transcription, repair, and recombination. This leads to rapid bactericidal activity.
3. Indications & Uses
- Acute infectious diarrhea (bacterial etiology suspected)
- Traveler's diarrhea
- Acute gastroenteritis with watery diarrhea
4. Dosage & Administration
Adult Dosage: One tablet (Racecadotril 15mg + Ofloxacin 50mg) twice daily. Typically prescribed for 3-5 days, not to exceed 7 days.
Administration: Administer with or without food. Take with a full glass of water. Maintain adequate fluid intake with ORS to prevent dehydration. Do not crush or chew. Complete the full prescribed course even if symptoms improve earlier.
5. Side Effects
Common side effects may include:
- Nausea
- Headache
- Dizziness
- Dry mouth
- Constipation (due to reduced fluid secretion)
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Antacids (Al, Mg, Ca), Sucralfate, Iron/Zinc supplements | Markedly reduced absorption of Ofloxacin due to chelation | Major |
| NSAIDs (e.g., Ibuprofen, Diclofenac) | Increased risk of CNS stimulation and seizures | Moderate |
| Corticosteroids (e.g., Prednisolone) | Increased risk of tendon rupture with Ofloxacin | Major |
| Oral Anticoagulants (Warfarin) | Ofloxacin may enhance anticoagulant effect; increased INR | Moderate |
| Theophylline | Ofloxacin may increase Theophylline levels, risk of toxicity | Moderate |
| Probenecid | Inhibits renal secretion of Ofloxacin, increasing its levels | Moderate |
| Antiarrhythmics (Class IA, III e.g., Amiodarone) | Additive QT prolongation, risk of arrhythmias | Major |
7. Patient Counselling
- DO take with plenty of water and continue Oral Rehydration Solution (ORS).
- DO complete the full course as prescribed.
- DO maintain a 2-hour gap between this medicine and antacids, iron, calcium, or zinc supplements.
- DO report any tendon pain, swelling, or difficulty walking immediately.
- DONT take for simple, non-infectious diarrhea or for more than 7 days without consulting a doctor.
- DONT give this medicine to children or adolescents.
- DONT drive or operate machinery if you feel dizzy.
8. Toxicology & Storage
Overdose: Nausea, vomiting, CNS excitation (agitation, confusion, seizures - from ofloxacin), crystalluria (with dehydration), acute renal injury. Symptoms of racecadotril overdose are expected to be minimal due to its mechanism.
Storage: Store below 30°C. Protect from light and moisture. Keep in the original blister pack until use. Keep out of reach of children.