A fixed-dose combination of a nitroimidazole antimicrobial (Ornidazole) and an amebicidal luminal agent (Diloxanide). Primarily used for the treatment of intestinal and hepatic amebiasis, giardiasis, and other anaerobic infections. Ornidazole acts systemically against trophozoites, while Diloxanide acts locally within the intestinal lumen against cysts and trophozoites, providing a synergistic and comprehensive anti-amebic effect.
Adult: One tablet (Ornidazole 250mg + Diloxanide 375mg) three times daily for 5-10 days. For hepatic amebiasis: Often prescribed for 10 days.
Note: Take after food to minimize GI upset. Swallow whole with a full glass of water. Complete the full prescribed course even if symptoms improve earlier.
Ornidazole: After entering the microbial cell, its nitro group is reduced by nitroreductase enzymes, generating cytotoxic intermediates that damage DNA, inhibit nucleic acid synthesis, and cause cell death. Diloxanide: Directly amebicidal, likely by interfering with protein synthesis and disrupting the parasite's microtubule structure. Its poor absorption ensures high intraluminal concentration.
Pregnancy: Category C (US FDA). Contraindicated in first trimester. Use in second/third trimester only if potential benefit justifies potential fetal risk. Ornidazole crosses the placenta.
Driving: May cause dizziness, drowsiness, or visual disturbances. Patients should not drive or operate machinery if affected.
| Alcohol | Disulfiram-like reaction (flushing, tachycardia, nausea, vomiting) | Major |
| Warfarin & other Coumarin anticoagulants | Ornidazole may inhibit metabolism, increasing anticoagulant effect and risk of bleeding | Major |
| Lithium | Ornidazole may increase lithium levels, risk of toxicity | Moderate |
| Phenobarbital, Phenytoin, Rifampicin | Enzyme inducers may reduce Ornidazole plasma levels | Moderate |
| Cyclosporine, Tacrolimus | Ornidazole may increase levels of these calcineurin inhibitors | Moderate |
Same composition (Ornidazole (250mg) + Diloxanide (375mg)), different brands: