Which substance is a calcium-based phosphate binder commonly used in CKD?

Which substance is a calcium-based phosphate binder commonly used in CKD?

• A. Sevelamer
• B. Calcium carbonate
• C. Lanthanum carbonate
• D. Sucroferric oxyhydroxide

Answer: (B)

In CKD, controlling phosphate starts with binders that stay in the gut and trap dietary phosphate so it isn’t absorbed. A calcium-based binder does this by providing calcium ions that combine with phosphate to form insoluble calcium phosphate, which is excreted in the stool. Calcium carbonate is the classic example of a calcium-based phosphate binder and is commonly used because it effectively lowers phosphate when taken with meals and is inexpensive and readily available. The other options listed act as phosphate binders too, but they do not supply calcium. They’re used when avoiding additional calcium load is desirable, such as in patients at risk for hypercalcemia or vascular calcification. Calcium carbonate, however, directly contributes calcium, which is why it’s the correct calcium-based choice.

In CKD, controlling phosphate starts with binders that stay in the gut and trap dietary phosphate so it isn’t absorbed. A calcium-based binder does this by providing calcium ions that combine with phosphate to form insoluble calcium phosphate, which is excreted in the stool. Calcium carbonate is the classic example of a calcium-based phosphate binder and is commonly used because it effectively lowers phosphate when taken with meals and is inexpensive and readily available.

The other options listed act as phosphate binders too, but they do not supply calcium. They’re used when avoiding additional calcium load is desirable, such as in patients at risk for hypercalcemia or vascular calcification. Calcium carbonate, however, directly contributes calcium, which is why it’s the correct calcium-based choice.