Packaging and storage—
Preserve in tight containers.
Labeling—
It may be labeled in terms of the weight of penicillin V contained therein, in addition to or instead of Units, on the basis that 1600 Penicillin V Units are equivalent to 1 mg of penicillin V.
Identification—
The retention time of the penicillin V peak in the chromatogram of the
Assay preparation corresponds to that in the chromatogram of the
Standard preparation, as obtained in the
Assay.
pH 
791
:
between 5.0 and 7.5, when constituted as directed in the labeling.
Assay—
Mobile phase, Standard preparation, Resolution solution, and Chromatographic system—
Proceed as directed in the
Assay under
Penicillin V.
Assay preparation—
Transfer an accurately measured volume of Penicillin V Potassium for Oral Solution, constituted as directed in the labeling, equivalent to about 400,000 USP Penicillin V Units, to a 100-mL volumetric flask, dilute with Mobile phase to volume, and mix. Filter a portion of this solution through a suitable filter having a 0.5-µm or finer porosity, and use the filtrate as the Assay preparation.
Procedure—
Proceed as directed for
Procedure in the
Assay under
Penicillin V. Calculate the number of USP Penicillin V Units in each mL of the constituted Penicillin V Potassium for Oral Solution taken by the formula:
100(CP / V)(rU / rS),
in which
V is the volume, in mL, of constituted Penicillin V Potassium for Oral Suspension taken, and the other terms are as defined therein.
