Ondansetron Hydrochloride Oral Suspension
» Ondansetron Hydrochloride Oral Suspension is a suspension of Ondansetron Hydrochloride. It contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of ondansetron (C18H19N3O), calculated on the anhydrous basis. Prepare Ondansetron Hydrochloride Oral Suspension 1.0 mg of Ondansetron Hydrochloride (dihydrate) equivalent to 0.8 mg of Ondansetron per mL as follows (see Pharmaceutical Compounding—Nonsterile Preparations 795):
Ondansetron (as Hydrochloride dihydrate) 80 mg
Vehicle: a mixture of Vehicle for Oral Suspension, NF, and Vehicle for Oral Solution, (regular or sugar-free), NF (1:1), a sufficient quantity  
to make 100 mL
If using Tablets, place the Tablets in a suitable glass mortar, and comminute well, or add Ondansetron Hydrochloride powder. Add 50 mL of the mixed Vehicle in 5-mL portions, and mix well with each addition. Transfer the contents of the mortar, stepwise and quantitatively, to a calibrated bottle. Add sufficient Vehicle to bring the preparation to final volume, and mix well.
Packaging and storage— Preserve in tight, light-resistant containers. Store at controlled room temperature, or in a cold place.
Labeling— Label it to state that it is to be well shaken before use, and to state the beyond-use date. Label content as: Each mL of Ondansetron Hydrochloride Oral Suspension contains 1 mg of Ondansetron Hydrochloride (dihydrate) equivalent to 0.8 mg Ondansetron.
USP Reference standards 11
USP Ondansetron Hydrochloride RS Click to View Structure
pH 791: between 3.6 and 4.6.
Beyond-use date: 42 days after the day on which it was compounded.
Mobile phase— Prepare a filtered and degassed solution of 43 mM monobasic potassium phosphate buffer adjusted with a mixture of 1 N sodium hydroxide and acetonitrile (85:15) to a pH of 5.4. Make adjustments if necessary (see System Suitability under Chromatography 621).
Standard preparation— Dissolve an accurately weighed quantity of USP Ondansetron Hydrochloride RS in Mobile phase to obtain a solution having a known concentration of about 4 µg per mL.
Assay preparation— After each amber plastic vial containing Oral Suspension that is stored at 4 is brought to room temperature, pipet 500 µL of Oral Suspension from each bottle into a 100-mL volumetric flask, and dilute with Mobile phase to volume. Pass through a 0.45-µm filter, and keep frozen at –70 until assayed.
Chromatographic system (see Chromatography 621)— The liquid chromatograph is equipped with a 216-nm detector, a 3.9-mm × 20-mm guard column that contains 4-µm packing L10, and a 4.6-mm × 25-cm analytical column that contains 5-µm packing L10. The flow rate is about 1 mL per minute. Chromatograph the Standard preparation, and record the peak responses as directed for Procedure: the retention time is about 30 minutes for ondansetron hydrochloride; and the relative standard deviation for replicate injections is not more than 1.6%.
Procedure— Separately inject equal volumes (about 80 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of ondansetron hydrochloride (C18H19N3O·HCl·2H2O) in the volume of Oral Suspension taken by the formula:
200(C/V)(rU / rS)
in which C is the concentration, in µg per mL, of USP Ondansetron Hydrochloride RS in the Standard preparation; V is the volume, in mL, of Oral Suspension taken; and rU and rS are the peak responses obtained from the Assay preparation and the Standard preparation, respectively.
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Monograph Jeanne H. Sun
Assistant Scientific Liaison
(CMP2010) Compounding
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USP35–NF30 Page 4120
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