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Alumina, Magnesia, and Calcium Carbonate Tablets
» Alumina, Magnesia, and Calcium Carbonate Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amounts of aluminum hydroxide [Al(OH)3], magnesium hydroxide [Mg(OH)2], and calcium carbonate (CaCO3).
Packaging and storage— Preserve in well-closed containers.
Labeling— Label the Tablets to indicate that they are to be chewed before being swallowed. Tablets prepared with the use of Dried Aluminum Hydroxide may be labeled to state the aluminum hydroxide content in terms of the equivalent amount of dried aluminum hydroxide gel, on the basis that each mg of dried gel is equivalent to 0.765 mg of Al(OH)3.
Identification— To a 3-g portion of finely powdered Tablets add 25 mL of water and 25 mL of 2 N sulfuric acid, stir, and heat on a steam bath for 10 minutes. Cool, add 50 mL of alcohol, and stir: the mixture so obtained responds to Identification tests A, B, and C under Alumina, Magnesia, and Calcium Carbonate Oral Suspension, beginning under Identification test A with “place in an ice bath for 30 minutes.”
Disintegration 701: 45 minutes.
Uniformity of dosage units 905: meet the requirements for Weight Variation with respect to alumina, to magnesia, and to calcium carbonate.
Acid-neutralizing capacity 301— Not less than 5 mEq of acid is consumed by the minimum single dose recommended in the labeling, and not less than the number of mEq calculated by the formula:
0.55(0.0385A) + 0.8(0.0343 M) + 0.9(0.02C),
in which 0.0385, 0.0343, and 0.02 are the theoretical acid-neutralizing capacities, in mEq, of Al(OH)3, Mg(OH)2, and CaCO3, respectively, and A, M, and C are the respective quantities, in mg, of Al(OH)3, Mg(OH)2, and CaCO3 in the specimen tested, based on the labeled quantities.
Residual solvents 467: meet the requirements.
(Official January 1, 2007)
Assay for aluminum hydroxide—
Edetate disodium titrant— Prepare as directed in the Assay for aluminum hydroxide under Alumina, Magnesia, and Calcium Carbonate Oral Suspension.
Assay preparation— Weigh and finely powder not fewer than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 600 mg of aluminum hydroxide, to a beaker, add 20 mL of water, and slowly add 40 mL of 3 N hydrochloric acid, with mixing. Heat the mixture to boiling, cool, and filter into a 200-mL volumetric flask. Wash the beaker with water, adding the washings to the filter. Add water to volume, and mix.
Procedure— Proceed as directed for Procedure in the Assay for aluminum hydroxide under Alumina, Magnesia, and Calcium Carbonate Oral Suspension. Each mL of 0.05 M Edetate disodium titrant is equivalent to 3.900 mg of Al(OH)3.
Assay for magnesium hydroxide—
Edetate disodium titrant and Assay preparation—Prepare as directed in the Assay for aluminum hydroxide.
Procedure— Proceed as directed for Procedure in the Assay for magnesium hydroxide under Alumina, Magnesia, and Calcium Carbonate Oral Suspension. Each mL of 0.05 M edetate disodium is equivalent to 2.916 mg of Mg(OH)2.
Assay for calcium carbonate—
Edetate disodium titrant and Assay preparation—Prepare as directed in the Assay for aluminum hydroxide.
Procedure— Proceed as directed for Procedure in the Assay for calcium carbonate under Alumina, Magnesia, and Calcium Carbonate Oral Suspension. Each mL of 0.05 M edetate disodium is equivalent to 5.004 mg of CaCO3.
Auxiliary Information— Staff Liaison : Elena Gonikberg, Ph.D., Scientist
Expert Committee : (MDGRE05) Monograph Development-Gastrointestinal Renal and Endocrine
USP29–NF24 Page 88
Pharmacopeial Forum : Volume No. 29(6) Page 1836
Phone Number : 1-301-816-8251