Metronidazole injection is available as a 5-mg/mL ready-to-use solution in 100-mL (500-mg) single-dose polyvinyl chloride (PVC)3798 or ethylene-propylene copolymer containers.3799 No dilution or buffering is required.3798; 3799 Each 100-mL of solution in PVC containers also contains dibasic sodium phosphate 48 mg, citric acid anhydrous 23 mg, and sodium chloride 790 mg in water for injection.3798 Each 100-mL of solution in ethylene-propylene copolymer containers also contains dibasic sodium phosphate 112 mg, citric acid anhydrous 40 mg, and sodium chloride 740 mg in water for injection.3799
pH
Metronidazole injection has a pH of 5.53798 or 5.83799 (ranging from 4.5 to 7).3798
Osmolarity
Metronidazole injection is isotonic; depending on the formulation, the solution has a calculated osmolarity of 3103798 or 297 mOsm/L.3799
Sodium Content
Metronidazole injection contains approximately 14 mEq of sodium per 500 mg of metronidazole.3798; 3799
Metronidazole injection is administered by continuous intravenous infusion or by intermittent intravenous infusion over 1 hour.3798; 3799
Equipment containing aluminum (e.g., needles, cannulae) must not come in contact with metronidazole injection because precipitation may occur.3798; 3799
Intact containers of metronidazole injection should be stored at controlled room temperature and protected from light until time of use.3798; 3799 The injection should not be refrigerated.3798; 3799 Freezing also should be avoided.3799
Precipitates may form if metronidazole injection comes in contact with equipment containing aluminum (e.g., needles, cannulae).3798
Sorption
Metronidazole was shown not to exhibit sorption to PVC bags and tubing, polyethylene tubing, Silastic tubing, and polypropylene syringes.536; 606
Central Venous Catheter
Metronidazole (Baxter) 5 mg/mL in dextrose 5% was found to be compatible with the ARROWg+ard Blue Plus (Arrow International) chlorhexidine-bearing triple-lumen central catheter. Essentially complete delivery of the drug was found with little or no drug loss occurring. Furthermore, chlorhexidine delivered from the catheter remained at trace amounts with no substantial increase due to the delivery of the drug through the catheter.2335
Y-Site Injection Compatibility (1:1 Mixture)
Additional Compatibility Information
Ceftriaxone Sodium
The admixture of ceftriaxone sodium 10 mg/mL and metronidazole (Flagyl, Searle) at concentrations not exceeding 5 to 7.5 mg/mL in sodium chloride 0.9% or dextrose 5% is stated to be stable for 24 hours at room temperature.3749 Precipitation occurs if the admixture is refrigerated.3749 Precipitation occurs at metronidazole concentrations greater than 8 mg/mL.3749
For a list of references cited in the text of this monograph, search the monograph titled References.