Metronidazole Injection, USP is a sterile, nonpyrogenic, isotonic, buffered parenteral dosage form of metronidazole in water for injection.
Each 100 mL contains metronidazole 500 mg (5 mg/mL) and sodium chloride 790 mg in water for injection; with dibasic sodium phosphate (anhydrous) 48 mg and citric acid (anhydrous) 23 mg added as buffers. The osmolarity of this solution is 314 mOsmol/liter (calc.). Each 100 mL contains 14 mEq sodium, pH 5.8 (4.5 ― 7.0).
Metronidazole is classified as a synthetic antibacterial and antiprotozoal agent and is administered by the intravenous route.
Metronidazole, USP is chemically designated 2-methyl-5-nitroimidazole-1-ethanol (C6H9N3O3), a crystalline powder sparingly soluble in water. It has the following structural formula:
Sodium Chloride, USP is chemically designated NaCl, a white crystalline powder freely soluble in water.
Water for Injection, USP is chemically designated H2O.
The flexible plastic container is fabricated from a specially formulated polyvinylchloride. Water can permeate from inside the container into the overwrap but not in amounts sufficient to affect the solution significantly. Solutions inside the plastic container also can leach out certain of its chemical components in very small amounts before the expiration period is attained. However, the safety of the plastic has been confirmed by tests in animals according to USP biological standards for plastic containers.