Terfenadine Tablets
Action and use
Histamine H1 receptor antagonist; antihistamine.
Definition
Terfenadine Tablets contain Terfenadine.
Content of terfenadine, C32H41NO2
95.0 to 105.0% of the stated amount.
Identification
Tests
Dissolution
Comply with the requirements for Monographs of the British Pharmacopoeia in the dissolution test for tablets and capsules, Appendix XII B1.
The chromatographic conditions described under Assay may be used but with a detection wavelength of 217 nm.
Calculate the total content of terfenadine, C32H41NO2, in the medium using the declared content of C32H41NO2 in terfenadine BPCRS.
1-[4-(1,1-Dimethylethyl)phenyl]-4-[4-(hydroxydiphenylmethyl)piperidin-1-yl]butan-1-one
Carry out the method for liquid chromatography, Appendix III D, using the following solutions.
The chromatographic conditions described under Assay may be used but using a detection wavelength of 217 nm.
The test is not valid unless, in the chromatogram obtained with solution (3), the resolution factor between the peaks is due to terfenadine and terfenadine impurity A is at least 5.0.
In the chromatogram obtained with solution (1):
the area of any peak corresponding to terfenadine impurity A is not greater than the area of the principal peak in the chromatogram obtained with solution (2) (0.2%).
Assay
Weigh and finely powder 20 tablets. Carry out the method for liquid chromatography, Appendix III D, using the following solutions.
In the chromatogram obtained with solution (1) peaks due to excipients with long retention times may be present.
Dilute 3 volumes of acetonitrile to 5 volumes with diethylammonium phosphate buffer solution pH 6.0.
The test is not valid unless, in the chromatogram obtained with solution (3), the resolution factor between the peaks due to terfenadine and terfenadine impurity A is at least 5.0.
Calculate the content of C32H41NO2 in the tablets using the declared content of C32H41NO2 in terfenadine BPCRS.