Sodium phosphates, IV

Dosage Forms & Strengths

Contains mixture of monobasic sodium phosphate and dibasic sodium phosphate

intravenous solution

• Phosphorus content: 93mg (3mM)/mL
• Sodium content: 92mg (4 mEq)/mL

Hypophosphatemia

The dose and administration IV infusion rate for sodium phosphates are dependent upon individual needs of the patient

Phosphorous serum level <0.5 mg/dL: 0.5 mmol/kg IV infused over 4-6 hr

Phosphorous serum level 0.5-1 mg/dL: 0.25 mmol/kg IV infused over 4-6 hr

Prevention of hypophosphatemia (eg, in TPN): 20-40 mmol/day IV admixed in TPN is typical dose, but adjustment according to electrolyte levels is ongoing

Administration

Calculate concomitant amount of sodium that will be administered: Each 1 mmol of phosphate contains ~1.3 mEq of sodium; if amount of sodium to be delivered is a concern (ie, sodium serum level >145 mEq/L), consider use of potassium phosphates IV to replete phosphorous level

Renal Impairment

Administration of solutions containing sodium and phosphorous in patients with impaired renal function may result in hypernatremia or hyperphosphatemia

Dosage Forms & Strengths

Contains mixture of monobasic sodium phosphate and dibasic sodium phosphate

intravenous solution

• Phosphorus content: 93mg (3mM)/mL
• Sodium content: 92mg (4 mEq)/mL

Hypophosphatemia

Caution should be exercised in premature neonates due to aluminum toxicity

The dose and administration IV infusion rate for sodium phosphates are dependent upon individual needs of the patient

Phosphorous serum level <0.5 mg/dL: 0.5 mmol/kg IV infused over 4-6 hr

Phosphorous serum level 0.5-1 mg/dL: 0.25 mmol/kg IV infused over 4-6 hr

Prevention of hypophosphatemia (eg, in TPN)

• Infants/children: 0.5-2 mmol/kg/day IV
• Children >50 kg or adolescents: 10-40 mmol/day IV
• Dose adjustment according to electrolyte levels is ongoing

Administration

Calculate concomitant amount of sodium that will be administered: Each 1 mmol of phosphate contains ~1.3 mEq of sodium; if amount of sodium to be delivered is a concern (ie, sodium serum level >145 mEq/L), consider use of potassium phosphates IV to replete phosphorous level

Renal Impairment

Administration of solutions containing sodium and phosphorous in patients with impaired renal function may result in hypernatremia or hyperphosphatemia

Pregnancy Category: C

Lactation: Unknown whether distributed in breast milk

Pregnancy Categories

A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA:Information not available.

Mechanism of Action

Phosphorus is involved in many biochemical functions in the body and significant metabolic and enzyme reactions in almost all organs and tissues; it exerts a modifying influence on the steady state of calcium levels, a buffering effect on acid-base equilibrium, and a primary role in the renal excretion of hydrogen ion

Sodium is the principal cation of extracellular fluid and comprises >90% of the total cations in the body; it is critical to regulating extracellular and intravascular volume

Elimination

Excretion: feces (10%), urine (90%)

IV Incompatibilities

Calcium and phosphorous are incompatible and will precipitate in most aqueous solutions; may be mixed in some TPN admixtures in variable quantities depending on the composition of the preparation, order of mixing, pH, temperature, storage, and particular calcium salt (consult pharmacist)

Y-Site Administration

• Acyclovir, amiodarone, amphotericin B lipid complex (Abelcet), amphotericin B liposome (AmBisome), anidulafungin, caspofungin, ciprofloxacin, daunorubicin liposome, doripenem, doxacurium, doxorubicin, epirubicin, gemtuzumab ozogamicin, idarubicin, ifosfamide, ketamine, lansoprazole, leucovorin calcium, lorazepam, mitoxantrone, mycophenolate, pantoprazole, quinupristin/dalfopristin, rocuronium

Admixture

• Ciprofloxacin, dobutamine

Syringe

• Aminophylline, pantoprazole, salbutamol

For Dilution

• D10% in 0.9% NaCl; D2.5% in Half-strength LR; D5% in LR; Dextrose 5% in Ringer's; Lactated Ringer's; Ringer's injection

IV Compatibilities

Y-Site Administration

• Alemtuzumab, aminocaproic acid, argatroban, atenolol, bivalirudin, bleomycin, carboplatin, carmustine, cisplatin, cyclophosphamide, cytarabine, dactinomycin, daptomycin, dexmedetomidine, dexrazoxane, diltiazem

Admixture

• Magnesium sulfate, metoclopramide, verapamil

For Dilution

• Dextran 70 6% in D5W; dextran 70 6% in 0.5% NaCl; D10W; D2.5W; D2.5/0.45% NaCl; D5/0.2% NaCl; D5/0.45% NaCl; D5/NS; 0.9% NaCl (NS); 0.45% NaCl; sodium lactate 1/6 M

IV Administration

Administered IV only after dilution in a larger volume of fluid

Administer slowly over 4-6 hr

Storage

Store at 20- 25°C (68- 77°F); excursions permitted to 15-30°C (59-86°F)

Does not contain a bacteriostatic agent or other preservatives; discard any unused portion