Loperamide Hydrochloride Oral Solution
» Loperamide Hydrochloride Oral Solution contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of loperamide hydrochloride (C29H33ClN2O2·HCl).
Packaging and storage Preserve in tight, light-resistant containers. Store below 40, preferably between 15 and 30, unless otherwise specified by the manufacturer.
USP Reference standards 11
A: Infrared Absorption 197K
Test specimen Transfer a volume of Oral Solution, equivalent to about 24 mg of loperamide hydrochloride, to a separator containing about 100 mL of water and 1 mL of sodium hydroxide solution (1 in 2), and gently swirl the contents. Add 50 mL of methylene chloride, shake gently by hand, releasing pressure often, and then shake by mechanical means for 20 minutes. Allow the layers to separate. Transfer the lower methylene chloride layer to a separator containing 100 mL of water. Shake gently by hand, releasing pressure often, and then shake by mechanical means for 10 minutes. Allow the layers to separate. Transfer the lower methylene chloride layer to a 250-mL beaker, and evaporate on a steam bath with the aid of a current of air to dryness. Add 10 mL of methanol and 500 mg of potassium bromide to the beaker, and mix. Evaporate on a steam bath with the aid of a current of air to dryness, and use the residue.
B: The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.
Uniformity of dosage units 905
for oral solution packaged in single-unit containers: meets the requirements.
Deliverable volume 698
for oral solution packaged in multiple-unit containers: meets the requirements.
pH 791: between 2.7 and 6.5.
Alcohol content, Method II 611 (if present): between 90.0% and 110.0% of the labeled amount of C2H5OH is found.
Buffer solution Transfer 3.0 g of monobasic potassium phosphate to a 1-L volumetric flask, dissolve in and dilute with water to volume, and mix.
Mobile phase Prepare a mixture of Buffer solution and acetonitrile (63:37), and adjust with 0.9 M phosphoric acid to a pH of 3.0. Mix, filter, and degas. Make adjustments if necessary (see System Suitability under Chromatography 621).
Standard preparation Dissolve an accurately weighed quantity of USP Loperamide Hydrochloride RS in methanol to obtain a solution having a known concentration of about 2 mg per mL. Quantitatively dilute this solution with water to obtain a solution having a known concentration of about 0.1 mg per mL. Further dilute this solution with Mobile phase to obtain a solution having a known concentration of about 10 µg of loperamide hydrochloride per mL.
Assay preparation Transfer an accurately measured volume of Oral Solution, equivalent to about 1.0 mg of loperamide hydrochloride, to a 100-mL volumetric flask. Dilute with Mobile phase to volume, mix, and filter.
Chromatographic system (see Chromatography 621) The liquid chromatograph is equipped with a 214-nm detector and a 4.0-mm × 8.0-cm column that contains 5-µm packing L7. The flow rate is about 1.5 mL per minute. Chromatograph the Standard preparation, and record the peak areas as directed for Procedure: the tailing factor is not more than 2.0; and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure Separately inject equal volumes (about 10 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the areas for the major peaks. Calculate the quantity, in mg, of loperamide hydrochloride (C29H33ClN2O2·HCl) in each mL of Oral Solution taken by the formula:
100(C/V)(rU / rS)in which C is the concentration, in mg per mL, of USP Loperamide Hydrochloride RS in the Standard preparation; V is the volume of Oral Solution taken to prepare the Assay preparation; and rU and rS are the peak areas obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 3705Pharmacopeial Forum: Volume No. 32(2) Page 353