What is the treatment for hyperphosphatemia (elevated phosphate levels)?

From the Guidelines

Hyperphosphatemia is primarily treated by reducing phosphate intake and increasing phosphate excretion, with the first step being to restrict dietary phosphate, aiming for less than 800-1000 mg per day, as supported by the most recent evidence from the Kidney Disease: Improving Global Outcomes 2017 clinical practice guideline update 1. The treatment approach should focus on patients with overt hyperphosphatemia, and phosphate-lowering therapies may only be indicated in the event of progressive or persistent hyperphosphatemia and not for prevention 1. Some key points to consider in the treatment of hyperphosphatemia include:

• Restricting dietary phosphate intake to less than 800-1000 mg per day, which involves limiting high-phosphate foods such as dairy products, nuts, and processed foods 1
• Using phosphate binders, such as calcium-based binders like calcium carbonate or non-calcium binders like sevelamer or lanthanum carbonate, to prevent phosphate absorption in the gut 1
• Increasing the frequency or duration of dialysis sessions to remove excess phosphate in patients with chronic kidney disease on dialysis 1
• Using intravenous fluids and loop diuretics to enhance phosphate excretion in cases of acute hyperphosphatemia 1
• Identifying and treating underlying causes, such as vitamin D toxicity or rhabdomyolysis, and regularly monitoring serum phosphate levels to adjust treatment as needed 1 It's also important to note that current evidence suggests that excess exposure to calcium may be harmful across all GFR categories of CKD, and phosphate-lowering treatment decisions should be individualized 1. The most recent and highest quality study, which is the Kidney Disease: Improving Global Outcomes 2017 clinical practice guideline update 1, provides the best evidence for the treatment of hyperphosphatemia, and its recommendations should be followed to prioritize morbidity, mortality, and quality of life as the outcome.

From the FDA Drug Label

Calcium acetate capsules are administered orally for the control of hyperphosphatemia in end-stage renal failure. Patients with ESRD retain phosphorus and can develop hyperphosphatemia. Calcium acetate, when taken with meals, combines with dietary phosphate to form an insoluble calcium phosphate complex, which is excreted in the feces, resulting in decreased serum phosphorus concentration.

The treatment for hyperphosphatemia (elevated phosphate levels) is calcium acetate or sevelamer, which act as phosphate binders to decrease serum phosphorus levels.

• Calcium acetate is administered orally, and its dose is adjusted as necessary to control serum phosphorus levels.
• Sevelamer also decreases serum phosphorus levels, and its average daily dose at the end of treatment was 4.9-6.5 g. Both treatments have been shown to significantly decrease mean serum phosphorus levels in patients with end-stage renal disease. 2, 3, 2

From the Research

Treatment Options for Hyperphosphatemia

The treatment for hyperphosphatemia involves several approaches, including:

• Dietary restriction of phosphorus intake, which may be achieved by decreasing protein intake and avoiding foods rich in phosphorus 4
• Use of phosphate binders to diminish intestinal phosphate absorption, with options including calcium-based salts, aluminum-containing agents, and non-calcium-based binders such as sevelamer, lanthanum carbonate, and magnesium salts 5, 6
• Efficient dialysis removal of phosphate in patients with chronic kidney disease (CKD) on dialysis 4, 5

Phosphate Binders

Phosphate binders are a crucial component of hyperphosphatemia treatment, with different types available, including:

• Calcium-based salts, which are effective but may lead to hypercalcemia and positive calcium balance 5, 6
• Non-calcium-based binders, such as sevelamer, lanthanum carbonate, and magnesium salts, which may be used as an alternative to calcium-based salts 5, 6
• New inhibitors of active intestinal phosphate transport, which may offer a promising approach to reducing serum phosphorus levels 6, 7

Dietary Restriction

Dietary restriction of phosphorus intake is essential in managing hyperphosphatemia, with a recommended daily intake of 750 mg or less 4

• This may be achieved by limiting protein intake to 45-50 g/day or 0.8 g/kg body weight/day for a 60 kg patient 4

Emerging Therapies

New treatment options are being developed to complement current therapies, including:

• Tenapanor, a novel sodium/hydrogen exchanger isoform 3 inhibitor that blocks the dominant paracellular phosphate absorption pathway 7