Metronidazol Fresenius (Metronidazole)

Metronidazole is employed to manage infections caused by anaerobic bacteria and certain protozoa.

• Anaerobic bacterial infections: eradicates susceptible anaerobes, reducing tissue damage and systemic spread.
• Bacterial vaginosis: restores normal vaginal flora by eliminating pathogenic anaerobes.
• Trichomoniasis: eliminates Trichomonas vaginalis, relieving symptoms and preventing recurrence.
• Amebic liver abscess: destroys Entamoeba histolytica trophozoites, aiding resolution of hepatic lesions.
• Clostridioides difficile infection: suppresses toxin‑producing C. difficile, helping to control colitis.

• Metronidazole enters susceptible microorganisms and is reduced by anaerobic cellular proteins to generate nitro radical anions. These reactive intermediates damage DNA and inhibit nucleic acid synthesis, leading to bacterial or protozoal cell death while sparing most aerobic host cells.

Metronidazole may cause a range of adverse reactions.

Common Side Effects

• Nausea: mild to moderate upset stomach.
• Metallic taste: transient metallic sensation in the mouth.
• Headache: occasional dull or throbbing pain.
• Diarrhea: loose stools, usually self‑limiting.
• Abdominal pain: cramping or discomfort in the abdomen.
• Dizziness: light‑headed feeling, especially on standing.

Serious or Rare Side Effects

• Seizures: rare neurologic events requiring immediate care.
• Peripheral neuropathy: tingling or numbness in extremities.
• Severe allergic reactions: rash, swelling, or anaphylaxis.
• Stevens‑Johnson syndrome: serious skin detachment.
• Hepatic toxicity: elevated liver enzymes or hepatitis.
• Neutropenia: marked reduction in white blood cells.

Before initiating therapy, consider the following safety measures.

• Renal function assessment: adjust therapy if severe impairment exists.
• Hepatic monitoring: check liver enzymes periodically during prolonged use.
• Alcohol avoidance: abstain to prevent disulfiram‑like reactions.
• Pregnancy caution: use only if benefits outweigh potential risks.
• Dose adjustment in hepatic impairment: reduce dose according to clinical judgment.
• Store at ambient temperature: keep in original container, protect from moisture and light.

Metronidazole can interact with several medicines; awareness helps prevent adverse outcomes.

Major Interactions (Avoid)

• Alcohol: may cause severe flushing, tachycardia, and nausea.
• Warfarin: potentiates anticoagulant effect, increasing bleeding risk.
• Lithium: can raise lithium levels, leading to toxicity.

Moderate Interactions (Monitor Closely)

• Cimetidine: may increase metronidazole plasma concentrations.
• Carbamazepine: may reduce metronidazole effectiveness.
• Oral contraceptives: may lower contraceptive efficacy, requiring additional protection.