Metronidazole Noridem Enterprises (Metronidazole)

Metronidazole is a nitroimidazole antibiotic used to treat infections caused by anaerobic bacteria and certain protozoa.

• Bacterial vaginosis: eliminates the anaerobic bacterial overgrowth responsible for the condition.
• Trichomoniasis: eradicates Trichomonas vaginalis, relieving symptoms and preventing recurrence.
• Amoebiasis: destroys Entamoeba histolytica trophozoites in intestinal and extra‑intestinal disease.
• Anaerobic bacterial infections: provides bactericidal activity against a broad range of anaerobes in tissues and organs.
• Clostridioides difficile infection: reduces toxin‑producing C. difficile bacteria in the colon.
• Pelvic inflammatory disease: treats mixed anaerobic infections contributing to PID.

• Metronidazole enters susceptible anaerobic microorganisms and is reduced by intracellular ferredoxin proteins to reactive nitro radical anions. These radicals interact with DNA, causing strand breakage and loss of helical structure, and they also inhibit nucleic acid synthesis. The resulting damage leads to bacterial and protozoal cell death, providing a bactericidal and protozoicidal effect.

Metronidazole may cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Metallic taste: transient metallic sensation in the mouth.
• Headache: mild headache during therapy.
• Diarrhea: loose stools that may be self‑limiting.
• Abdominal pain: cramping or discomfort in the abdomen.
• Dizziness: occasional light‑headedness.

Serious or Rare Side Effects

• Seizures: rare neurologic events requiring immediate attention.
• Severe allergic reactions: including anaphylaxis, rash, or swelling.
• Stevens‑Johnson syndrome: serious skin and mucous membrane involvement.
• Peripheral neuropathy: tingling or numbness, potentially irreversible.
• Neutropenia: marked reduction in white blood cells.
• Hepatotoxicity: elevated liver enzymes or liver injury.

Before initiating Metronidazole therapy, consider the following precautions to ensure safe use.

• Renal impairment: adjust dosing and monitor renal function.
• Hepatic impairment: use with caution and observe liver enzymes.
• Alcohol consumption: avoid alcohol due to a disulfiram‑like reaction.
• Pregnancy: prescribe only when benefits outweigh potential risks.
• Concurrent warfarin therapy: monitor INR closely for enhanced anticoagulation.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze.

Metronidazole can interact with several medicines; awareness of major and moderate interactions helps prevent adverse outcomes.

Major Interactions (Avoid)

• Alcohol: may cause severe flushing, tachycardia, and nausea.
• Warfarin: increased anticoagulant effect, requiring INR monitoring.
• Lithium: heightened lithium toxicity, necessitating serum level checks.
• Live vaccines: reduced efficacy of attenuated organisms.
• Carbamazepine: may lower metronidazole concentrations, reducing effectiveness.

Moderate Interactions (Monitor Closely)

• Phenytoin: possible reduction in metronidazole levels.
• Rifampin: enzyme induction may decrease metronidazole exposure.