Isoniazid Injection
» Isoniazid Injection is a sterile solution of Isoniazid in Water for Injection. It contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of C6H7N3O.
Packaging and storage— Preserve in single-dose or in multiple-dose containers, preferably of Type I glass, protected from light.
Labeling— Its package label states that if crystallization has occurred, the Injection should be warmed to redissolve the crystals prior to use.
USP Reference standards 11
USP Isoniazid RS Click to View Structure
USP Endotoxin RS
A: The retention time exhibited by isoniazid in the chromatogram of the Assay preparation corresponds to that of isoniazid in the chromatogram of the Standard preparation as obtained in the Assay.
B: A volume of Injection, equivalent to about 50 mg of isoniazid, responds to Identification test B under Isoniazid.
Bacterial endotoxins 85 It contains not more than 0.3 USP Endotoxin Unit per mg of isoniazid.
pH 791: between 6.0 and 7.0.
Other requirements— It meets the requirements under Injections 1.
Mobile phase , Standard preparation, and Chromatographic system—Proceed as directed in the Assay under Isoniazid.
Assay preparation— Transfer an accurately measured volume of Injection, equivalent to about 100 mg of isoniazid, to a 50-mL volumetric flask. Dilute with Mobile phase to volume, and mix. Transfer 8.0 mL of this solution to a 50-mL volumetric flask, dilute with Mobile phase to volume, and mix.
Procedure— Proceed as directed for Procedure in the Assay under Isoniazid. Calculate the quantity, in mg, of C6H7N3O in each mL of the Injection taken by the formula:
312.5(C / V)(rU / rS)
in which C is the concentration, in mg per mL, of USP Isoniazid RS in the Standard preparation; V is the volume, in mL, of Injection taken; and rU and rS are the peak responses of isoniazid obtained from the Assay preparation and the Standard preparation, respectively.
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Topic/Question Contact Expert Committee
Monograph Behnam Davani, Ph.D., M.B.A.
Senior Scientific Liaison
(SM12010) Monographs - Small Molecules 1
Reference Standards RS Technical Services
85 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
(GCM2010) General Chapters - Microbiology
USP35–NF30 Page 3575