1. Clinical Overview
A fixed-dose combination (FDC) drug used for the treatment of acute infectious diarrhea. Racecadotril is an enkephalinase inhibitor with antisecretory action, reducing fluid and electrolyte loss. Ofloxacin is a broad-spectrum fluoroquinolone antibiotic effective against common bacterial enteropathogens. This combination addresses both the symptom (watery diarrhea) and the cause (bacterial infection) in indicated cases.
| Onset | Duration | Bioavailability |
|---|---|---|
| Racecadotril: 30-60 minutes for antisecretory effect. Ofloxacin: Systemic absorption begins within 1 hour; antibacterial effect at site of infection depends on local concentration. | Racecadotril: Approximately 6-8 hours per dose. Ofloxacin: Dosing interval is 12 hours due to its half-life. | Racecadotril (as active metabolite thiorphan): ~10% (low, but sufficient for local gut action). Ofloxacin: ~95-100%. |
2. Mechanism of Action
Racecadotril acts as a prodrug, converted to thiorphan, which inhibits membrane-bound enkephalinase in the intestinal epithelium. This inhibition prevents the breakdown of endogenous enkephalins, which in turn activate delta-opioid receptors. Receptor activation inhibits adenylate cyclase, reducing cyclic AMP levels and subsequent hypersecretion of water and electrolytes into the gut lumen. It does not affect 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 bacterial diarrhea in adults (caused by susceptible organisms like E. coli, Shigella spp., Salmonella spp., Campylobacter jejuni).
- Traveler's diarrhea of suspected bacterial origin.
4. Dosage & Administration
Adult Dosage: One tablet (Racecadotril 100mg + Ofloxacin 200mg) twice daily. Typically prescribed for 3-5 days, not to exceed 7 days.
Administration: Take tablet with or without food. Swallow whole with a full glass of water. Maintain adequate hydration with Oral Rehydration Solution (ORS) to prevent dehydration. Do not take with dairy products, calcium-fortified juices, or antacids containing calcium, magnesium, or aluminum (take Ofloxacin at least 2 hours before or 4 hours after these).
5. Side Effects
Common side effects may include:
- Nausea
- Headache
- Dizziness
- Abdominal pain/discomfort
- Dry mouth
- Skin rash/itching
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, especially in elderly | Major |
| Oral Anticoagulants (Warfarin) | Ofloxacin may enhance anticoagulant effect; increased INR risk | Moderate |
| Theophylline | Ofloxacin inhibits its metabolism; increased theophylline toxicity risk | Major |
| Probenecid | Reduces renal secretion of Ofloxacin, increasing its blood levels | Moderate |
| Antiarrhythmics (Amiodarone, Sotalol), Antipsychotics | Additive QT prolongation risk, leading to Torsades de Pointes | Major |
| Oral Hypoglycemics (Sulfonylureas) | Ofloxacin may enhance hypoglycemic effect | Moderate |
7. Patient Counselling
- DO take the tablet with a full glass of water.
- DO complete the full prescribed course even if you feel better.
- DO use Oral Rehydration Solution (ORS) liberally to prevent dehydration.
- DO take Ofloxacin at least 2 hours before or 4 hours after antacids, dairy, or mineral supplements.
- DONT give this medicine to children or adolescents.
- DONT take it if you are pregnant, planning pregnancy, or breastfeeding.
- DONT engage in strenuous exercise; report any tendon pain or swelling immediately.
- DONT drive or operate heavy machinery if you feel dizzy.
8. Toxicology & Storage
Overdose: Nausea, vomiting, CNS excitation (agitation, confusion, hallucinations, convulsions), acute renal failure, QT prolongation leading to arrhythmias. Crystalluria may occur with Ofloxacin overdose due to its low solubility at alkaline pH.
Storage: Store below 30°C. Protect from light and moisture. Keep in the original blister pack or container. Keep out of reach of children. Do not use after the expiry date printed on the pack.