From the Guidelines
Medications that cause the most concern for hyperphosphatemia include phosphate-containing laxatives, phosphate enemas, vitamin D supplements, and phosphate-containing medications like sodium phosphate bowel preparations. These medications can rapidly increase serum phosphate levels, especially in patients with impaired kidney function, and are particularly concerning in patients with chronic kidney disease, as their reduced ability to excrete phosphate makes them more susceptible to developing dangerous hyperphosphatemia 1. Some key points to consider when evaluating the risk of hyperphosphatemia from medications include:
- Phosphate-containing laxatives such as Fleet Phospho-Soda can cause a rapid increase in serum phosphate levels
- Vitamin D analogs (calcitriol, paricalcitol) can indirectly raise phosphate levels by increasing intestinal phosphate absorption
- Certain antacids containing aluminum hydroxide with calcium carbonate or magnesium hydroxide can contribute to phosphate retention
- Bisphosphonates used for osteoporosis treatment may temporarily elevate phosphate levels
- Intravenous phosphate replacement solutions can cause iatrogenic hyperphosphatemia if administered too rapidly or in excessive amounts It is essential to carefully select medications and monitor phosphate levels in patients with renal impairment to prevent hyperphosphatemia and its associated morbidity and mortality 1. The most recent and highest quality study, published in 2018 in the Annals of Internal Medicine, provides guidance on the diagnosis, evaluation, prevention, and treatment of chronic kidney disease-mineral and bone disorder, and highlights the importance of careful medication selection and monitoring in patients with chronic kidney disease 1.
From the FDA Drug Label
Administration of calcitriol to patients in excess of their daily requirements can cause hypercalcemia, hypercalciuria, and hyperphosphatemia. Calcitriol increases inorganic phosphate levels in serum The administration of calcitriol to patients in excess of their daily requirements can cause hypercalcemia, hypercalciuria, and hyperphosphatemia.
The medications that cause the most concern for hyperphosphatemia are:
- Calcitriol (PO): due to its potential to increase inorganic phosphate levels in serum, especially in patients with renal failure 2 2 Key points to consider:
- Dose and administration: excessive doses of calcitriol can lead to hyperphosphatemia
- Patient population: patients with renal failure are at higher risk of developing hyperphosphatemia due to calcitriol treatment
- Monitoring: regular monitoring of serum phosphorus levels is necessary to prevent hyperphosphatemia in patients taking calcitriol 2 2
From the Research
Medications Causing Concern for Hyperphosphatemia
The following medications and substances have been associated with an increased risk of hyperphosphatemia:
- Phosphate-containing oral laxatives, such as Fleet Phospho-Soda, which can cause severe hyperphosphatemia, especially in the elderly or those with renal insufficiency 3
- Aluminum-containing phosphate binders, which are effective but have toxic risks 4, 5
- Calcium-based phosphate binders, which can lead to hypercalcemia, positive calcium balance, and progression of cardiovascular calcification 4, 5, 6
- Lanthanum carbonate, which is effective but may have long-term effects on tissue deposition 4, 5, 6, 7
- Sevelamer, which is effective but may have gastrointestinal side effects and bind bile acids 4, 5, 6, 7
- Iron preparations, which can bind phosphate but may have significant systemic absorption of the iron component 4
Key Considerations
When selecting a phosphate binder, it is essential to consider the potential risks and benefits, including: