Edition: BP 2025 (Ph. Eur. 11.6 update)
Chewable Calcium Carbonate and Heavy Magnesium Carbonate Tablets
Action and use
Antacid.
DEFINITION
Calcium Carbonate and Heavy Magnesium Carbonate Chewable Tablets contain Calcium Carbonate and Heavy Magnesium Carbonate. They may be flavoured.
The tablets comply with the requirements stated under Tablets and with the following requirements.
Content of Calcium, Ca
95.0 to 105.0% of the stated amount.
Content of magnesium, Mg
95.0 to 105.0% of the stated amount.
IDENTIFICATION
A. In the Assay, solution (1) exhibits a similar absorption to the standard solutions at 422.7 nm (calcium).
B. In the Assay, solution (3) exhibits a similar absorption to the standard solutions at 285.2 nm (magnesium).
C. The powdered tablets yield reaction B characteristic of calcium salts, Appendix VI.
D. The powdered tablets yield reaction B characteristic of magnesium and magnesium salts, Appendix VI.
E. The powdered tablets yield the reactions characteristic of carbonates, Appendix VI.
TESTS
Disintegration
The requirement for Disintegration does not apply to Calcium Carbonate and Heavy Magnesium Carbonate Chewable Tablets.
ASSAY
For calcium
Weigh and powder 20 tablets. For solution (1) disperse a quantity of the powdered tablets containing the equivalent of 0.272 g of calcium in 10 mL of 6M hydrochloric acid, stir for 15 minutes, and add sufficient water to produce 500 mL, mix and filter. To 1 volume of the filtrate add 5 volumes of lanthanum trioxide solution and dilute to 100 volumes with water.
Prepare the standard solutions using a suitable volume of calcium standard solution (1000 ppm Ca) add 10 mL of 6M hydrochloric acid, and sufficient water to produce 500 mL, mix and filter. To 1 volume of the filtrate add 5 volumes of lanthanum trioxide solution and dilute to 100 volumes with water.
For solution (2) to 10 mL of 6M hydrochloric acid add sufficient water to produce 500 mL, mix and filter. To 1 volume of the filtrate add 5 volumes of lanthanum trioxide solution and dilute to 100 volumes with water.
Determine the total content of calcium in solution (1) by Method I for atomic absorption spectrophotometry, Appendix II D, measuring at 422.7 nm using the standard solutions and solution (2) as the blank.
For magnesium
Weigh and powder 20 tablets. For solution (3) disperse a quantity of the powdered tablets containing the equivalent of 22 mg of magnesium in 10 mL of 6M hydrochloric acid, stir for 15 minutes and add sufficient water to produce 500 mL, mix and filter. To 1 volume of the filtrate add 5 volumes of lanthanum trioxide solution and dilute to 100 volumes with water.
Prepare the standard solutions using a suitable volume of magnesium standard solution (100 ppm Mg), add 10 mL of 6M hydrochloric acid and sufficient water to produce 500 mL, mix and filter. To 1 volume of the filtrate add 5 volumes of lanthanum trioxide solution and dilute to 100 volumes with water.
Determine the total content of magnesium in solution (3) by Method I for atomic absorption spectrophotometry, Appendix II D, measuring at 285.2 nm using the standard solutions and solution (2) as the blank.
STORAGE
Calcium Carbonate and Heavy Magnesium Carbonate Chewable Tablets should be protected from moisture.
LABELLING
The quantity of active ingredient is stated in terms of the equivalent amount of calcium and magnesium.
