• Therapeutic Category
  • Pharmaceutical Form : Tablets
  • Composition : Metronidazole 500 mg /Tab
  • Active Substance : Metronidazole

Mechanism of action:

Once Metronidazole enters the organism, it is reduced by electron transport proteins. Thus, a concentration gradient is created which promotes the drug’s intracellular transport. Presumably, free radicals are formed which react with cellular components resulting in death of the bacteria.


Absorption: Following oral administration, Metronidazole is well absorbed with peak plasma concentrations occurring between 1-2 hours after administration.

Distribution: Less than 20% of the circulating Metronidazole is bound to plasma proteins.

Metabolism: Metronidazole is metabolized by side-chain oxidation, which results in the formation of the active hydroxyl metabolite, and glucuronide conjugation.

Excretion: The major route of elimination of the drug and its metabolites is via the urine; its renal clearance is approximately 10 mL/min/1.73 m2. The average elimination half-life is 8 hours.


METRONIDAZOLE is indicated for:

  1. Treatment of symptomatic Trichomoniasis in females and males when the presence of the trichomonad has been confirmed, and asymptomatic Trichomoniasis in females when it‘s associated with endocervicitis, cervicitis, or cervical erosion. Asymptomatic sexual partners of treated patients should be treated simultaneously to prevent reinfection of the partner.
  2. Treatment of acute intestinal amebiasis (amebic dysentery) and amebic liver abscess.
  3. Treatment of Anaerobic Bacterial Infections that are proven or strongly suspected to be caused by susceptible bacteria.


Patients with history of hypersensitivity to Metronidazole or other nitroimidazole derivatives.


headache, syncope, dizziness, vertigo, ataxia, irritability, depression, weakness, insomnia, nausea, anorexia, vomiting, diarrhea, abdominal cramps, constipation, unpleasant metallic taste, glossitis, urticaria, rash, pruritus, neutropenia (rarely), thrombocytopenia, Stevens-Johnson Syndrome, nasal congestion, dryness of the mouth and vagina, fever, dysuria, polyuria, proliferation of Candida in the vagina, decrease of libido, proctitis, fleeting joint pains, rare cases of pancreatitis.


  • Metronidazole should not be given to patients who have taken Disulfiram within the last two weeks.
  • Alcoholic beverages and products containing propylene glycol should be avoided during Metronidazole therapy.
  • Metronidazole may elevate the serum Lithium when they are co-administered.
  • Cimetidine may prolong the half-life of Metronidazole. Phenytoin or Phenobarbital may reduce plasma levels of Metronidazole.


  • Cases of aseptic meningitis, encephalopathy, peripheral neuropathy (including optic neuropathy) which is characterized by numbness or paresthesia of an extremity, and convulsive seizures have been reported with Metronidazole. The appearance of abnormal neurologic symptoms demands prompt evaluation of the continuation of therapy.
  • The drug should be taken as directed; skipping doses or not completing the full course of therapy may decrease the effectiveness of treatment and increase the likelihood of developing bacterial resistance.
  • Metronidazole may interfere with certain types of test values, such as AST, ALT, LDH, triglycerides, and glucose hexokinase.


As Metronidazole crosses the placental barrier, its use in pregnancy should be carefully evaluated. The drug is contraindicated during the first trimester of pregnancy. A decision should be made whether to discontinue the drug or to discontinue nursing during its use.


Trichomoniasis: 2 g given either as a single dose or in 2 divided doses of 1 g each, given in the same day or 250 mg 3 times daily for seven consecutive days. The dosage regimen should be individualized.

Amebiasis: For acute intestinal amebiasis: 750 mg orally 3 times daily for 5 to 10 days.For amebic liver abscess: 500 mg or 750 mg orally 3 times daily for 5 to 10 days.

Anaerobic Bacterial Infections: In most serious anaerobic infections, intravenous Metronidazole is usually administered initially. The usual oral dosage is 500 mg every 6 hours for 7 to 10 days; however, infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.

For patients with severe hepatic impairment, the dose should be reduced by 50%.

In elderly, and patients with decreased renal function monitoring for Metronidazole associated adverse events is recommended.

Supplementation of Metronidazole dose following hemodialysis should be considered.


Symptoms of overdosage include: nausea, vomiting, and ataxia. There is no specific antidote for Metronidazole overdose; management should consist of symptomatic and supportive therapy.

PACKAGING:Pack contains 20 Tablets

STORAGE CONDIIONS :Store at (20 -25) °C, protect from light