VHOSPITAL.CLINIC · Parasite Treatment Drug
Metronidazole is the gold-standard treatment for giardiasis, achieving cure rates of 85–95% with a standard 5–7 day course.
Metronidazole is a nitroimidazole that is reduced inside Giardia trophozoites to form toxic radical intermediates, which damage DNA and disrupt cellular respiration — killing the parasite.
Adults: 250–500 mg three times daily for 5–7 days. Children: 5 mg/kg three times daily for 5–7 days. Take with food to reduce nausea.
This is a general reference. Always follow your physician's prescription and local treatment guidelines.
Most patients notice improvement within 2–3 days of starting metronidazole. Diarrhoea and bloating typically resolve within 5–7 days. The full course must be completed to prevent recurrence.
Yes. Treatment failure occurs in up to 15% of cases, often due to re-infection or emerging resistance. Tinidazole or a second metronidazole course are used for retreatment.
Metronidazole inhibits aldehyde dehydrogenase, causing acetaldehyde accumulation when alcohol is consumed — producing flushing, nausea, vomiting, and palpitations (disulfiram-like reaction).
Metronidazole treats Giardiasis, which can cause these symptoms:
Explore our medical library for comprehensive treatment protocols, drug comparisons, prevention strategies, and resistance patterns.
Get a structured AI clinical assessment — possible parasitic causes, red flags, and next steps based on your symptoms.
Start Free AI Analysis →Content on this page is informed by evidence-based clinical sources including: