Erythromycin Stearate Tablets
Action and use
Macrolide antibacterial.
Definition
Erythromycin Stearate Tablets contain Erythromycin Stearate.
Identification
Tests
Dissolution
Comply with the requirements for Monographs of the British Pharmacopoeia in the dissolution test for tablets and capsules, Appendix XII B1, using Apparatus 2. Use as the medium 900 mL of a 2.722% w/v solution of sodium acetate, the pH of which has been adjusted to 5.0 with glacial acetic acid and rotate the paddle at 50 revolutions per minute. Transfer 5 mL of a filtered sample to a graduated flask, add 40 mL of glacial acetic acid and 10 mL of a 0.5% w/v solution of 4-dimethylaminobenzaldehyde in glacial acetic acid and dilute to 100 mL with a mixture of 35 volumes of glacial acetic acid and 70 volumes of hydrochloric acid. Allow to stand for 15 minutes and measure the absorbance of the resulting solution at the maximum at 485 nm, Appendix II B, using in the reference cell dissolution medium that has been subjected to the conditions of the test. Prepare a suitable solution of erythromycin stearate BPCRS in the dissolution medium and filter. Transfer 5 mL of the filtered solution to a graduated flask, add 40 mL of glacial acetic acid and 10 mL of a 0.5% w/v solution of 4-dimethylaminobenzaldehyde in glacial acetic acid and dilute to 100 mL with a mixture of 35 volumes of glacial acetic acid and 70 volumes of hydrochloric acid. Allow to stand for 15 minutes and measure the absorbance of the resulting solution at the maximum at 485 nm, Appendix II B, using in the reference cell dissolution medium that has been subjected to the conditions of the test. Calculate the total content of C37H67NO13 in the medium from the absorbances obtained using the declared content of C37H67NO13 in erythromycin stearate BPCRS.
Assay
Weigh and powder 20 tablets. Dissolve a quantity of the powder containing the equivalent of 25 mg of erythromycin as completely as possible in sufficient methanol to produce 100 mL and carry out the microbiological assay of antibiotics for erythromycin, Appendix XIV A. The precision of the assay is such that the fiducial limits of error are not less than 95% and not more than 105% of the estimated potency. Calculate the content of erythromycin in the tablets, taking each 1000 IU found to be equivalent to 1 mg of erythromycin. The upper fiducial limit of error is not less than 97.0% and the lower fiducial limit of error is not more than 110.0% of the stated content.
Storage
Erythromycin Stearate Tablets should be protected from light.
Labelling
The quantity of active ingredient is stated in terms of the equivalent amount of erythromycin.