Packaging and storage—
Preserve in well-closed containers.
Labeling—
Tablets 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—
A:
Place a quantity of finely ground Tablets, equivalent to about 500 mg of aluminum hydroxide, in a flask equipped with a stopper and glass tubing, the tip of which is immersed in
calcium hydroxide TS in a test tube. Add 5 mL of 3 N hydrochloric acid to the flask, and immediately insert the stopper: gas evolves in the flask and a precipitate is formed in the test tube.
B:
The solution remaining in the flask responds to the tests for
Aluminum 
191
.
Disintegration 701:
10 minutes, simulated gastric fluid TS being substituted for water in the test.
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 55.0% of the expected mEq value, calculated from the labeled quantity of Al(OH)
3, is obtained. Each mg of Al(OH)
3 has an expected acid-neutralizing capacity value of 0.0385 mEq.
Assay—
Edetate disodium titrant—
Prepare and standardize as directed in the
Assay under
Ammonium Alum.
Procedure—
Weigh and finely powder not fewer than 20 Tablets. Weigh accurately a portion of the powder, equivalent to about 1.2 g of aluminum hydroxide, add 15 mL of hydrochloric acid, and heat until dissolved. Dilute with water to about 100 mL, mix, and filter quantitatively into a 500-mL volumetric flask, washing the filter with water. Proceed as directed in the
Assay under
Dried Aluminum Hydroxide Gel, beginning with “dilute with water to volume.” Each mL of 0.05 M
Edetate disodium titrant is equivalent to 3.900 mg of Al(OH)
3.
