Metronidazolo Kabi (Metronidazole)

Metronidazole is employed to manage infections caused by anaerobic bacteria and susceptible protozoa. It is indicated for several clinical conditions:

• Anaerobic bacterial infections: eradicates susceptible anaerobes, reducing infection severity.
• Bacterial vaginosis: restores normal vaginal flora by eliminating pathogenic anaerobes.
• Trichomoniasis: eliminates Trichomonas vaginalis, relieving symptoms.
• Amoebic dysentery: kills Entamoeba histolytica trophozoites, controlling intestinal disease.
• Clostridioides difficile infection (adjunct): reduces toxin‑producing bacterial load when used with standard therapy.

• Metronidazole is taken up by anaerobic microorganisms and reduced by intracellular electron transport proteins to reactive nitro radicals. These radicals covalently bind to DNA and other macromolecules, causing strand breakage and loss of cellular function, ultimately leading to microbial cell death.

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

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Metallic taste: transient alteration of taste perception.
• Headache: mild to moderate intensity.
• Diarrhea: loose stools, usually self‑limiting.
• Abdominal pain: cramping or discomfort.
• Dizziness: occasional light‑headedness.

Serious or Rare Side Effects

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

Metronidazole requires careful use in specific patient populations and clinical situations.

• Renal impairment: assess renal function and adjust therapy as needed.
• Hepatic dysfunction: monitor liver enzymes during treatment.
• Pregnancy Category B: use only when clearly indicated.
• Alcohol consumption: avoid to prevent disulfiram‑like reactions.
• Concurrent antibiotics: evaluate for additive toxicity.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze.

Metronidazole interacts with several medicines; some combinations should be avoided while others need monitoring.

Major Interactions (Avoid)

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

Moderate Interactions (Monitor Closely)

• Oral contraceptives: may reduce efficacy, consider backup method.
• Cimetidine: can increase metronidazole plasma concentrations.
• Rifampin: may lower metronidazole levels, reducing effectiveness.