Metronidazole dosage and administration
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Chetan Lokhande, M.B.B.S [2]
DOSAGE AND ADMINISTRATION
Trichomoniasis
- In the Female: Seven-day course of treatment (375 mg two times daily for seven consecutive days).
A seven-day course of treatment may minimize reinfection by protecting the patient long enough for the sexual contacts to obtain treatment. Pregnant patients should not be treated during the first trimester (see Contraindications and Precautions).
When repeat courses of the drug are required, it is recommended that an interval of four to six weeks elapse between courses and that the presence of the trichomonad be reconfirmed by appropriate laboratory measures. Total and differential leukocyte counts should be made before and after re-treatment.
- In the Male: Treatment should be individualized as it is for the female.
Amebiasis
Adults
For acute intestinal amebiasis (acute amebic dysentery): 750 mg orally three times daily for 5 to 10 days.
For amebic liver abscess: 750 mg orally three times daily for 5 to 10 days.
Pediatric patients
35 to 50 mg/kg/24 hours, divided into three doses, orally for 10 days.
Anaerobic Bacterial Infections
In the treatment of most serious anaerobic infections, intravenous metronidazole is usually administered initially.
The usual adult oral dosage is 7.5 mg/kg every 6 hours (approximately 500 mg for a 70 kg adult). A maximum of 4 g should not be exceeded during a 24-hour period.
The usual duration of therapy is 7 to 10 days; however, infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.
Dosage Adjustments
Patients with Severe Hepatic impairment
For amebiasis patients with severe (Child-Pugh C) hepatic impairment, pharmacokinetic modeling and simulation indicate that the FLAGYL 375 capsules dose should be reduced by 50%. Therefore, the dosage regimen of FLAGYL 375 capsules inChild Pugh C patients with amebiasis is 375 mg q8h for 5 to 10 days (see Clinical Pharmacology and Precautions).
For trichomoniasis patients with severe (Child-Pugh C) hepatic impairment, pharmacokinetic modeling and simulation indicate that the frequency of metronidazole administration should be reduced from every12 hours to every 24 hours. Therefore, the dosage regiment of FLAYGL 375 capsules in Child Pugh C patients with trichomoniasis is 375 mg q24h for 7 days (see Clinical Pharmacology and Precautions).
Patients Undergoing Hemodialysis
Hemodialysis removes significant amounts of metronidazole and its metabolites from systemic circulation. The clearance of metronidazole will depend on the type of dialysis membrane used, the duration of the dialysis session, and other factors. If the administration of metronidazole cannot be separated from a hemodialysis session, supplementation of metronidazole dosage following the hemodialysis session should be considered, depending on the patient's clinical situation (see Clinical Pharmacology).[1]
References
Adapted from the FDA Package Insert.