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Metronidazole

Also sold as Metronidazole, metronidazole, metronidazole vaginal

Medicine summary · from official FDA labels · Oct 19, 2026

Serious warning: Metronidazole has been shown to be carcinogenic in mice and rats (see PRECAUTIONS ). Unnecessary use of the drug should be avoided.
2 recalls on record — a recall affects specific batches; check with your pharmacist.

What it’s used for

Symptomatic Trichomoniasis. Metronidazole tablets are indicated for the treatment of T.

How to take it

Trichomoniasis: In the Female: One-day treatment − two grams of metronidazole tablets, given either as a single dose or in two divided doses of one gram each, given in the same day. Seven-day course of treatment − 250 mg three times daily for seven consecutive days.

Important warnings

Hypersensitivity Reactions Hypersensitivity reactions including severe cutaneous adverse reactions (SCARs) can be serious and potentially life threatening (see ADVERSE REACTIONS ). Severe Cutaneous Adverse Reactions Severe cutaneous adverse reactions (SCARs) including toxic epidermal necrolysis (TEN), Stevens-Johnson syndrome (SJS), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) have been reported with the use of metronidazole.

Common side effects

The following reactions have been reported during treatment with metronidazole: Central Nervous System: The most serious adverse reactions reported in patients treated with metronidazole have been convulsive seizures, encephalopathy, aseptic meningitis, optic and peripheral neuropathy, the latter characterized mainly by numbness or paresthesia of an extremity. Since persistent peripheral neuropathy has been reported in some patients receiving prolonged administration of metronidazole, patients should be specifically warned about these reactions and should be told to stop the drug and report immediately to their physicians if any neurologic symptoms occur.

Interactions

Drug Interactions Disulfiram Psychotic reactions have been reported in alcoholic patients who are using metronidazole and disulfiram concurrently.

If pregnant or breastfeeding

Pregnancy: Teratogenic Effects There are no adequate and well controlled studies of metronidazole in pregnant women.

Forms & strengths

40 MG/ML Oral Suspension · 375 MG Oral Capsule · 200 MG Oral Tablet · 400 MG Oral Tablet · 500 MG Rectal Suppository · 0.008 MG Topical Gel · 1000 MG Rectal Suppository · 100 MG/ML Oral Suspension · 125 MG Oral Tablet · 7.5 MG/ML Topical Cream · 0.0075 MG Topical Gel · 10 MG/ML Topical Cream · 500 MG Oral Tablet · 250 MG Oral Tablet · 0.01 MG Topical Gel

Questions to ask your doctor or pharmacist

  • Is this the right medicine for my condition, and how long should I take it?
  • What side effects should I watch for, and which need urgent attention?
  • Does this interact with my other medicines, supplements, or alcohol?
  • What should I do if I miss a dose or take too much?