Ornidazole is a 5-nitroimidazole derivative active against protozoa and anaerobic bacteria. It is converted to reduction products that interact with DNA to cause destruction of helical DNA structure and strand leading to a protein synthesis inhibition and cell death in susceptible organisms.

Ornidazole is indicated for Amoebiasis (Intestinal and hepatic), Giardiasis, Trichomoniasis, Bacterial vaginosis, Treatment of susceptible anaerobic infections

Amoebiasis:

• Adults: 500 mg twice a day for 5 days.
• Children: 10-25 mg per kg body weight in two divided doses.

Amoebic dysentery:

• Adults: 1.5 gm once a day for 3 days.
• Children: 40 mg per kg body weight, once a day for 3 days.

Giardiasis:

• Adults: 1.5 gm once daily for 1-2 days.
• Children: 40 mg per kg body weight for 2 days.

Trichomoniasis: 1.5 gm once or 500 mg twice a day for 5 days. Sexual partner should also be treated at the same time.

Bacterial vaginosis: 3 tablets of 500 mg each as a single dose or one tablet of 500 mg once daily for 5-7 days.

Previous hypersensitivity to Ornidazole and to other nitroimidazoles. Ornidazole is contraindicated in central nervous system disorders, particularly in epilepsy or in peripheral neuropathy.

Side effects of Ornidazole have been mainly limited to the gastrointestinal tract (nausea, vomiting, epigastric pain) and central nervous system (dizziness, headache, lassitude). Unlike other nitroimidazoles, Ornidazole does not interact with alcohol, although this requires further study.

Leukopenia has been described occasionally during therapy. Adverse central nervous system (CNS) effects of Ornidazole have mainly included headache, dizziness, lassitude or somnolence, fatigue and weakness. Adverse CNS effects of Ornidazole may be less than that happens with metronidazole. Seizures have not been reported with Ornidazole in studies available to date.

In patient with ataxia, vertigo, and mental confusion, Ornidazole should be prescribed with caution. During prolonged treatment with Ornidazole, blood dyscrasia namely mild leukopenia have been reported rarely. In case leukopenia occurs, the decision to discontinue the therapy should depend upon the gravity of infection.

Use in Special Populations

Renal Impairment Haemodialysis patients: Give a supplemental dose (50% of the usual dose) before dialysis.

Hepatic Impairment Severe: Double the interval between doses.

Pregnancy & Lactation

Adequate clinical trials have not been conducted. Ornidazole should be prescribed only if the potential benefit justifies the potential risk to fetus/neonate.