This protocol covers the management of hypophosphatemia at its most critical threshold — a plasma phosphate below 0.3 mmol/L — as well as any symptomatic presentation requiring urgent correction.

Clinical Scenario

Plasma phosphate < 0.3 mmol/L (severe), or symptomatic hypophosphatemia presenting with haemolysis, respiratory failure, cardiac arrhythmias, or weakness.

Severe < 0.3 mmol/L Moderate 0.3–0.5 mmol/L Mild 0.51–0.8 mmol/L

Treatment Approach

Correction involves intravenous phosphate administration. The specific preparation, concentration, infusion approach for standard and critically ill patients, and relevant precautions are detailed in the full protocol →

References

HYPOphosphataemia (Mild: 0.8–0.51 mmol/L, Moderate: 0.5–0.3 mmol/L, Severe: less than 0.3 mmol/L)

Severe or symptomatic hypophosphataemia (e.g. haemolysis, respiratory failure, cardiac arrhythmias, weakness)

Correct with intravenous phosphate.

Administer one ampoule (10 mmol) of sodium dihydrogen phosphate in 250 mL of 0.9% sodium chloride over 2 to 6 hours into a large vein.

More concentrated solutions can be given (preferably via a central line) (e.g. one ampoule [10 mmol] of sodium dihydrogen phosphate in 100 mL of 0.9% sodium chloride). Administer at rates up to 10 mmol per hour, maximum of 40 mmol over 4 hours. Caution when giving repeat doses in renal impairment.

View source ↗

Treatment of Severe or Symptomatic Hypophosphatemia (Plasma Phosphate < 0.3 mmol/L)