From the FDA Drug Label
Phosphorus 15 mmol/5 mL (3 mmol/mL) The amount of phosphate correction that 15 mmol IV of KPO4 would replace is 15 mmol of phosphorus 1.
From the Research
Intravenous administration of 15 mmol of potassium phosphate (KPO4) would provide approximately 15 mmol (or 465 mg) of phosphate replacement, which is expected to raise serum phosphate levels by about 0.5-0.7 mmol/L (1.5-2.0 mg/dL) in an average adult patient, as supported by the most recent study 2. The exact increase in serum phosphate will vary depending on the patient's weight, renal function, and the severity of hypophosphatemia.
- Factors influencing the increase in serum phosphate levels include:
- Patient's weight
- Renal function
- Severity of hypophosphatemia When administering IV phosphate, it should be given slowly, usually over 4-6 hours, to prevent complications such as hypocalcemia, hyperphosphatemia, or calcium-phosphate precipitation.
- Monitoring of serum phosphate, calcium, and renal function is essential during replacement therapy, as emphasized in 3. Phosphate is crucial for numerous cellular functions including ATP production, cell membrane integrity, and bone mineralization, making appropriate replacement important in deficiency states.
- For severe hypophosphatemia (less than 0.32 mmol/L or 1.0 mg/dL), higher doses or repeated administration may be necessary, as suggested by 4 and 5. The most recent study 2 highlights the importance of addressing hypophosphatemia in patients requiring continuous renal replacement therapy, and a preemptive approach to address hypophosphatemia, including aggressive supplementation strategies to correct phosphorus, is warranted in these patients.