From the Guidelines
Phosphate binders are medications used to treat hyperphosphatemia, primarily in patients with chronic kidney disease, and include calcium-based binders, non-calcium-based binders, and iron-based binders, with the choice of binder depending on individual patient factors, such as calcium load and risk of vascular calcification 1.
Types of Phosphate Binders
- Calcium-based binders, such as calcium carbonate and calcium acetate, which are typically first-line due to lower cost, but may increase calcium load and risk of vascular calcification 1
- Non-calcium-based binders, such as sevelamer carbonate, which may be preferred in patients with hypercalcemia or significant vascular calcification 1
- Iron-based binders, such as ferric citrate and sucroferric oxyhydroxide, which are also effective in binding dietary phosphate
Dosage and Administration
- Calcium-based binders: calcium carbonate 500-1500mg with meals, calcium acetate 667mg, 2-3 tablets with meals
- Non-calcium-based binders: sevelamer carbonate 800-1600mg with meals, lanthanum carbonate 500-1000mg with meals
- Iron-based binders: ferric citrate 1-2 tablets with meals, sucroferric oxyhydroxide 500mg with meals
Important Considerations
- Timing is crucial—these medications should be taken with meals to effectively bind dietary phosphate
- Regular monitoring of serum phosphate, calcium, and PTH levels is essential to adjust dosing
- Dietary phosphate restriction (800-1000mg/day) should accompany binder therapy for optimal management of hyperphosphatemia
- The total calcium intake from diet, calcium-containing phosphate binders, and dialysate should not exceed 2 g/day, as recommended by the K/DOQI guidelines 1
From the FDA Drug Label
Calcium acetate capsules are a phosphate binder indicated for the reduction of serum phosphorus in patients with end stage renal disease. Calcium acetate acts as a phosphate binder. Calcium acetate capsules are a phosphate binder indicated to reduce serum phosphorus in patients with end stage renal disease (ESRD).
Phosphate binders are medications that bind to phosphate in the gastrointestinal tract and reduce serum phosphorus levels.
- Key function: Reduce serum phosphorus in patients with end-stage renal disease.
- Example: Calcium acetate capsules 2, 2, 2.
From the Research
Definition and Purpose of Phosphate Binders
- Phosphate binders are medications used to treat hyperphosphatemia, a condition characterized by elevated levels of phosphate in the blood, often occurring in patients with chronic kidney disease (CKD) 3.
- The primary purpose of phosphate binders is to reduce intestinal phosphate absorption, thereby lowering serum phosphorus levels and mitigating the risks associated with hyperphosphatemia, such as cardiovascular morbidity and mortality 3.
Types of Phosphate Binders
- Calcium-based phosphate binders, such as calcium acetate and calcium carbonate, are commonly used due to their low cost and effectiveness in lowering serum phosphate levels [(3,4)].
- Non-calcium-based phosphate binders, including sevelamer, lanthanum carbonate, and magnesium salts, are alternative options that can be used when calcium-based binders are not suitable [(3,5)].
- Iron-based phosphate binders, such as sucroferric oxyhydroxide, are a newer class of medications that have shown promise in reducing phosphatemia with a similar safety profile to sevelamer 6.
Mechanism of Action and Efficacy
- Phosphate binders work by binding to phosphate in the gut, preventing its absorption into the bloodstream, and thereby reducing serum phosphorus levels [(3,5)].
- The efficacy of phosphate binders can vary depending on the type of binder, dose, and individual patient factors, such as renal function and dietary phosphate intake [(3,7)].
- Studies have shown that most phosphate binders are roughly equally effective in lowering serum phosphate concentrations, although some may have a slightly better safety profile or fewer side effects [(7,4)].