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Nortriptyline Hydrochloride Oral Solution
»Nortriptyline Hydrochloride Oral Solution contains nortriptyline hydrochloride equivalent to not less than 90.0percent and not more than 110.0percent of the labeled amount of nortriptyline (C19H21N).
Packaging and storage—
Preserve in tight,light-resistant containers.
Identification—
A:
Transfer a measured volume of Oral Solution,equivalent to about 50mg of nortriptyline hydrochloride,to a suitable separator,and render the solution distinctly alkaline (to a pHof 11or above as indicated by pHindicator paper)by the dropwise addition of 1Nsodium hydroxide.Extract with 15mLof chloroform,and filter the chloroform extract through about 2g of anhydrous sodium sulfate that has been previously washed with chloroform.Evaporate the chloroform extract with the aid of heat and a current of air to dryness,and dissolve the residue in 0.5mLof chloroform:the IRabsorption spectrum of this solution exhibits maxima only at the same wavelengths as that of a Standard solution obtained by dissolving 50mg of USP Nortriptyline Hydrochloride RSin 25mLof water and proceeding as directed for the test specimen.
B:
It responds to the tests for Chloride á191ñ,when tested as specified for alkaloidal hydrochlorides.
Uniformity of dosage units á905ñ—
FOR ORAL SOLUTION PACKAGED IN SINGLE-UNIT CONTAINERS:
meets the requirements.
Deliverable volume á698ñ—
FOR ORAL SOLUTION PACKAGED IN MULTIPLE-UNIT CONTAINERS:
meets the requirements.
pHá791ñ:
between 2.5and 4.0.
Assay—
Transfer an accurately measured volume of Oral Solution,equivalent to about 10mg of nortriptyline,to a 125-mLseparator.Add 20mLof water,mix,and render the solution distinctly alkaline (to a pHof 11or above as indicated by pHindicator paper)by the dropwise addition of sodium hydroxide solution (1in 2).Extract the nortriptyline with four 25-mLportions of chloroform,filtering each extract into a 250-mLbeaker through about 12g of anhydrous sodium sulfate previously washed with 25mLof chloroform.Rinse the sodium sulfate with four 5-mLportions of chloroform,and collect the rinsings in the beaker.Evaporate the combined chloroform solution with the aid of heat and a current of air to about 10mL.Transfer the contents of the beaker with the aid of chloroform to a 200-mLvolumetric flask.Evaporate the chloroform with the aid of air alone to dryness.[Caution—Do not use heat.
]Dissolve the residue in 1.7mLof hydrochloric acid,dilute with water to volume,and mix.Transfer 10.0mLof the solution to a 50-mLvolumetric flask,dilute with water to volume,and mix to obtain the Assay preparation.Concomitantly determine the absorbances of the Assay preparationand a Standard solution of USP Nortriptyline Hydrochloride RSin water having a known concentration of about 11.4µg per mLin 1-cm cells at the wavelength of maximum absorbance at about 239nm,with a suitable spectrophotometer,using water as the blank.Calculate the quantity,in mg,of C19H21Nin the portion of Oral Solution taken by the formula:
(263.38/299.85)(C)(AU/AS),
in which 263.38and 299.85are the molecular weights of nortriptyline and nortriptyline hydrochloride,respectively;Cis the concentration,in µg per mL,of USP Nortriptyline Hydrochloride RSin the Standard solution;and AUand ASare the absorbances of the Assay preparationand the Standard solution,respectively.
Auxiliary Information—
Staff Liaison:Salvador C.Salado,M.S.,Scientist and Latin American Liaison
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 1405
Pharmacopeial Forum:Volume No.29(6)Page 1939
Phone Number:1-301-816-8165
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