Amebiasis、Anaerobic bacterial infections

Amebicide
After diffusing into the organism, interacts with DNA to cause a loss of helical DNA structure and strand breakage resulting in inhibition of protein synthesis and cell death in susceptible organisms

Absorption well
Metabolism: Hepatic (30% to 60%) to several metabolites including an active hydroxyl metabolite
Half-life elimination:8hrs.

1. Treatment of bacterial vaginosis: same as the CDC recommended twice daily dose in nonpregnant females.
2. Treatment of vaginal trichomoniasis: Contraindicated during the first trimester. At other stage of pregnancy, CDC recommends the single oral dose regimen in pregnancy.
3. Treatment of giardiasis: some sources recommend second and third trimester administration only
4. Treatment of symptomatic amebiasis: recommend second and third trimester administration only.

Metronidazole present in breast milk.
whether to discontinue breastfeeding or to discontinue the drug，taking into account the importance of treatment to the mother.

1. >10%: Nausea、Vaginitis、Headache.
2. 1~10%: Genital pruritus、Flu-like symptoms、Abdominal pain、diarrhea、Dizziness

1.Amebiasis, intestinal (acute dysentery) or extraintestinal (liver abscess): 500 to 750 mg every 8 hours for 7 to 10 days followed by an intraluminal agent
2.Bacterial vaginosis: 500 mg twice daily for 7 days.

1. Amebiasis (Infants, Children, and Adolescents): 35 to 50 mg/kg/day in divided doses every 8 hours for 7 to 10 days; maximum dose: 750 mg/dose; for severe infection or extraintestinal disease, IV may be necessary
2. Bacterial vaginosis (Children >45 kg and Adolescents): 500 mg twice daily for 7 days.

1. CrCl >10 mL/minute: No dosage adjustment necessary; however, monitor closely for adverse effects due to accumulation of metabolites in patients with more severe impairment (CrCl <30 mL/minute), particularly with prolonged courses of therapy.
2. CrCl <10 mL/minute: No dosage adjustment necessary; however, monitor closely for adverse effects due to accumulation of metabolites.
3. Hemodialysis, intermittent (thrice weekly): Dialyzable, larger doses may be utilized depending on clinical indication, but with close monitoring for adverse effects, particularly if the treatment course is >1 to 2 weeks in duration. On dialysis days, administer after dialysis.
4. CRRT: No dosage adjustment necessary.

Mild or moderate impairment (Child-Pugh class A or B): No dosage adjustment necessary; use with caution and monitor for adverse events.
Severe impairment (Child-Pugh class C): Reduce dose by 50%.