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Thiothixene Hydrochloride Oral Solution
» Thiothixene Hydrochloride Oral Solution contains an amount of thiothixene hydrochloride equivalent to not less than 90.0 percent and not more than 110.0 percent of the labeled amount of thiothixene (C23H29N3O2S2).
Packaging and storage— Preserve in tight, light-resistant containers.
Identification— Transfer a portion of Oral Solution, equivalent to about 20 mg of thiothixene hydrochloride, to a separator containing 20.0 mL of chloroform. Render the aqueous layer just basic with ammonium hydroxide, shake for 1 minute, and allow the layers to separate. Pass a portion of the chloroform layer through filter paper, previously washed with chloroform; and use the clear filtrate for the test. Proceed as directed in the Identification test under Thiothixene Capsules, beginning with “Apply 10 µL of this test solution.”
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 2.0 and 3.0.
Alcohol content, Method II 611: if present, between 90.0% and 110.0% of the labeled amount, the labeled amount being not more than 7.0% of C2H5OH, determined by the gas-liquid chromatographic procedure, acetonitrile being used as the internal standard.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay— [NOTE—Perform the dilution operations in low-actinic glassware.]
Mobile phase, Standard preparation, and Chromatographic system— Prepare as directed in the Assay under Thiothixene.
Assay preparation— Transfer an accurately measured volume of Oral Solution, equivalent to about 25 mg of thiothixene, to a 25-mL volumetric flask; dissolve in and dilute with methanol to volume; and mix. Pipet 2 mL of this solution into a 100-mL volumetric flask, dilute with methanol to volume, and mix.
Procedure— Proceed as directed for Procedure in the Assay under Thiothixene. Calculate the quantity, in mg, of thiothixene (C23H29N3O2S2) in each mL of the Oral Solution taken by the formula:
(1250C/V)(rU / rS),
in which C is the concentration, in mg per mL, of USP Thiothixene RS in the Standard preparation; V is the volume, in mL, of Oral Solution taken; and rU and rS are the peak responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information— Staff Liaison : Ravi Ravichandran, Ph.D., Senior Scientist
Expert Committee : (MDPP05) Monograph Development-Psychiatrics and Psychoactives
USP29–NF24 Page 2138
Pharmacopeial Forum : Volume No. 29(6) Page 1993
Phone Number : 1-301-816-8330