tinidazole (P01AB02) — ATC Formulary

Forms & Strengths

Adult Dosing

Intestinal amebiasis: 2 g orally once daily for 3 days
Amebic liver abscess: 2 g orally once daily for 3 to 5 days
Giardiasis: 2 g orally as a single dose
Trichomoniasis: 2 g orally as a single dose (treat sexual partner simultaneously)
Bacterial vaginosis: 2 g orally once daily for 2 days or 1 g orally once daily for 5 days

Pediatric Dosing

Amebiasis (children > 3 years): 50 mg/kg/day (up to 2 g/day) for 3 consecutive days
Giardiasis (children > 3 years): 50 mg/kg (up to 2 g) as a single dose
Trichomoniasis (adolescents): 2 g orally as a single dose
Safety and efficacy in children under 3 years of age not established

Indications

Mechanism of Action

Synthetic 5-nitroimidazole derivative
Enters the microbial cell by passive diffusion
Reduction of the nitro group by trichomonad ferredoxin or bacterial nitroreductases forms reactive free radicals
Binds to and damages DNA, resulting in microbial cell death

Contraindications

Hypersensitivity to tinidazole, other nitroimidazole derivatives, or formulation components
First trimester of pregnancy (for trichomoniasis indication)
Patients with trichimoniasis with a history of blood dyscrasias

Adverse Reactions

Drug Interactions

Alcohol: Disulfiram-like reaction (flushing, vomiting, tachycardia); avoid alcohol during and for 3 days after therapy
Warfarin and other oral anticoagulants: Potentiation of anticoagulant effect and increased bleeding risk
CYP3A4 inducers (e.g., rifampin, phenytoin): May decrease plasma concentrations of tinidazole
CYP3A4 inhibitors (e.g., ketoconazole, erythromycin): May increase plasma concentrations of tinidazole
Lithium: May increase lithium serum levels and risk of toxicity