Phosphate

Recommended Daily Dietary Allownces (RDA) for Phosphate Expressed as phosphorus (31 mg = 1 mmole)
Age	RDA
£6 months	300 mg
6 to 12 months	500 mg
1 - 10 yrs	800 mg
11 - 24	1200 mg
25 - 55	800 mg
>55 yrs	?
Pregnant or Lactating female	1200 mg

Phosphate Supplementation
Degree of hypophosphatemia	Repletion Protocol
Mild (2.1 - 2.9 mg/dL) (0.8 - 0.9 mmoles/L)	Oral route is preferred (diary products or supplements; see table) IV (pt weighs ³ 60 kg): 9 mmoles IV over 6 hrs IV (pt weighs < 60 kg): 0.15 mmoles/kg IV over 6 hrs Check phosphate level and repeat dose as necessary
Moderate (1 - 2 mg/dL) (0.3 - 0.7 mmoles/L)	Oral route is preferred (diary products or supplements; see table below) IV (pt weighs ³ 60 kg): 12 mmoles IV over 6 hrs IV (pt weighs < 60 kg): 0.2 mmoles/kg IV over 6 hrs Check phosphate level and repeat dose as necessary
Severe (<1 mg/dL) (<0.3 mmoles/L)	IV (pt weighs ³ 60 kg): 15 mmoles IV over 6 hrs IV (pt weighs < 60 kg): 0.3 mmoles/kg IV over 6 hrs Check phosphate level and repeat dose as necessary
Phosphorus: 31 mg = 1 millimole; normal serum phosphorus level is 3 to 4.5 mg/dL (1 to 1.5 mmoles/L). When replacing phosphate, monitor the plasma levels of Mg and K and replete these electrolytes as necessary; hypomagnesemia and hypokalemia promote excessive phosphate excretion.

Oral Products for Phosphate Supplementation
	Elemental Phosphorus (mg)	Phosphate (mmoles)	Na+ (mEq)	K+ (mEq)
Milk (per mL)	0.9	0.029	0.025	0.035
Neutra-Phos (per packet)	250	8	7.1	7.1
Neutra-Phos K (per packet)	250	8	0	14.25
Fleet's Phospho-soda (per mL)	129	4.15	4.8	0
K-Phos (per tablet)	125	4	2.9	1.4

Parenteral Products for Phosphate Supplementation
	Elemental Phosphorus (mg/mL)	Phosphate (mmoles/mL)	Na+ (mEq/mL)	K+ (mEq/mL)
Na Phosphate	93	3	4	0
K Phosphate	93	3	0	4.4

References: Facts and Comparisons. St. Louis, Mo. Lippincott. 1998. Trissel's Handbook of Injectable Drugs. Bethesda, MD. ASHP. 1994. Baumgartner et al. Clinical Guide to Parenteral Micronutrition. 2nd Edition Fujisawa, USA. 1991.