Antibiotics: Metronidazole (Nitroimidazole)

Question 1

What is the mechanism of Metronidazole (Nitroimidazole)

Answer 1

Inhibitors of DNA synthesis (reduction of nitro group, active intermediates bind DNA & inhibit DNA synthesis)

Question 2

What is the spectrum of Metronidazole (Nitroimidazole)

Answer 2

• Anaerobes - Clostridium difficile, Bacteroides spp.
• Parasites - Trichomonas vaginalis ( bacterial vaginosis ), Entamoeba histolytica (amoebiasis), Giardia lamblia, Enterobius vermicularis (pinworm)

Question 3

What are the indications of Metronidazole (Nitroimidazole)

Answer 3

• Anaerobic infection e.g. intra abdominal, pelvic inflammatory disease
• Treatment of C. difficile colitis
• Parasitic infection e.g. bacterial vaginosis, amoebic liver abscess

Question 4

What are the adverse effects of Metronidazole (Nitroimidazole)

Answer 4

• GI: nausea, vomiting, diarrhoea, abdominal pain
• Metallic taste
• CNS: peripheral neuropathy with prolonged therapy
• Disulfiram like reaction with alcohol (nausea, vomiting, flushing, tachycardia, palpitations)