Potassium phosphates injection provides phosphorus 3 mmol/mL (potassium 4.4 mEq/mL).
The dosage is dependent upon the individual needs of the patient, and the contribution of phosphorus and potassium from other sources.
Initial or Single Dose
The phosphorus doses in Table 2 are general recommendations for an initial or single dose and are intended for most patients. Based upon clinical requirements, some patients may require a lower or higher dose. The maximum initial or single dose of phosphorus is 45 mmol (potassium 66 mEq) [see Warnings and Precautions (5.1)].
In patients with moderate renal impairment (eGFR ≥30 mL/min/1.73 m2 to <60 mL/min/1.73 m2), start at the low end of the dose range [see Use in Specific Populations (8.6)].
Monitor serum phosphorus, potassium, calcium and magnesium serum concentrations.
TABLE 2: Recommended Initial or Single Dose of Potassium Phosphates Injection in Intravenous Fluids to Correct Hypophosphatemia in Adults and Pediatric Patients
Serum Phosphorus Concentrationa
| Phosphorus Dosageb,c
| Corresponding Potassium Content
|
1.8 mg/dL to lower end of the reference range a
| 0.16 mmol/kg to 0.31 mmol/kg
| Potassium 0.23 mEq/kg to 0.46 mEq/kg
|
1 mg/dL to 1.7 mg/dL
| 0.32 mmol/kg to 0.43 mmol/kg
| Potassium 0.47 mEq/kg to 0.63 mEq/kg
|
Less than 1 mg/dL
| 0.44 mmol/kg to 0.64 mmol/kgc
| Potassium 0.64 mEq/kg to 0.94 mEq/kg
|
a Serum phosphorus reported using 2.5 mg/dL as the lower end of the reference range for healthy adults and pediatric patients 12 months of age and older. Serum phosphorus reported using 4 mg/dL as the lower end of the reference range for preterm and term infants less than 12 months of age. Serum phosphorus concentrations may vary depending on the assay used and the laboratory reference range.
b Weight is in terms of actual body weight. Limited information is available regarding dosing of patients significantly above ideal body weight; consider using an adjusted body weight for these patients.
c up to a maximum of phosphorus 45 mmol (potassium 66 mEq) as a single dose.
Concentration and Intravenous Infusion Rate
- The concentration of the diluted solution [see Table 1, Dosage and Administration (2.1)] and the infusion rate is dependent upon whether administration will be through a peripheral or central venous catheter. The maximum recommended infusion rates are shown in Table 3 for adults and pediatric patients 12 years of age and older.
TABLE 3: Maximum Recommended Infusion Rate of Potassium Phosphates Injection for Adults and Pediatric Patients 12 Years of Age and Older
Route of Administration
| Maximum Infusion Rate
|
Peripheral Venous Catheter
| phosphorus 6.8 mmol/hour (potassium 10 mEq/hour)
|
Central Venous Catheter
| phosphorus 15 mmol/hour (potassium 22 mEq/hour)
|
Continuous electrocardiographic (ECG) monitoring and infusion through a central venous catheter is recommended for infusion rates higher than:
- Potassium 10 mEq/hour for adults and pediatric patients weighing 20 kg or greater
- Potassium 0.5 mEq/kg/hour for pediatric patients weighing less than 20 kg
Repeated Dosing
Additional dose(s) following the initial dose may be needed in some patients. Prior to administration of additional doses, assess the patient clinically, obtain serum phosphorus, calcium and potassium concentrations and adjust the dose accordingly.