Dosing & Uses
Dosage Forms & Strengths
potassium phosphate/sodium phosphate
tablet
- 126mg/67mg
- 250mg/298mg
- 250mg/160mg
Hypophosphatemia
K-Phos Neutral: 1-2 tablets PO q4hr
Phos-NaK: 1 packet mixed with 75 mL water or juice
Low Urinary Phosphate
1-2 tablets PO q6hr
Dosage Modifications
Renal impairment: Use with caution in patients with chronic renal disease or renal function impairment
Dosage Forms & Strengths
potassium phosphate/sodium phosphate
tablet
- 126mg/67mg
- 250mg/298mg
- 250mg/160mg
Hypophosphatemia
<4 years: Safety and efficacy not established
≥4 years: K-Phos Neutral, 1 tablet PO q6hr; Phos-NaK, 1 packet PO q6hr mixed with 75 mL water or juice
Low Urinary Phosphate
<4 years: Safety and efficacy not established
≥4 years: 1-2 tablets PO q6hr
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Contraindicated (1)
- sodium phosphate rectal
sodium phosphate rectal, sodium acid phosphate. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Either increases toxicity of the other. Coadministration of various sodium phosphate preparations are known to cause electrolyte disturbances and hypovolemia.
Serious - Use Alternative (3)
- baloxavir marboxil
sodium acid phosphate will decrease the level or effect of baloxavir marboxil by cation binding in GI tract. Avoid or Use Alternate Drug. Baloxavir may bind to polyvalent cations resulting in decreased absorption. Studies in monkeys showed concurrent use with calcium, aluminum, or iron caused significantly decreased plasma levels. Human studies not conducted.
- erdafitinib
potassium phosphate, erdafitinib. Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid coadministration during initial dosing adjustment period (ie, first 21 days). Increases in serum phosphate levels are a pharmacodynamic effect of FGFR inhibition. Serum phosphate binders may obscure decisions regarding initial dosage increase.
- potassium phosphates, IV
potassium phosphate and potassium phosphates, IV both increase serum potassium. Avoid or Use Alternate Drug.
sodium acid phosphate and potassium phosphates, IV both increase serum potassium. Avoid or Use Alternate Drug.
Monitor Closely (10)
- deflazacort
sodium acid phosphate and deflazacort both decrease serum potassium. Use Caution/Monitor.
- dextroamphetamine
sodium acid phosphate decreases levels of dextroamphetamine by increasing renal clearance. Use Caution/Monitor.
- lisdexamfetamine
sodium acid phosphate decreases levels of lisdexamfetamine by increasing renal clearance. Use Caution/Monitor.
- magnesium supplement
magnesium supplement will decrease the level or effect of potassium phosphate by Other (see comment). Modify Therapy/Monitor Closely. Drug may form a chelate with divalent cations; may decrease absorption by the intestinal tract; applies to oral forms; separate administration of drugs to avoid interaction
- methamphetamine
sodium acid phosphate decreases levels of methamphetamine by increasing renal clearance. Use Caution/Monitor.
- methylenedioxymethamphetamine
sodium acid phosphate decreases levels of methylenedioxymethamphetamine by increasing renal clearance. Use Caution/Monitor.
- omadacycline
sodium acid phosphate will decrease the level or effect of omadacycline by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Multivalent cation-containing products may impair absorption of tetracyclines, which may decrease its efficacy. Separate dosing of tetracyclines from these products.
- potassium iodide
potassium iodide and potassium phosphate both increase serum potassium. Use Caution/Monitor.
- pseudoephedrine
potassium phosphate decreases effects of pseudoephedrine by unknown mechanism. Use Caution/Monitor. Urinary excretion of indirect acting alpha/beta agonists (eg, pseudoephedrine) may increase when administered concomitantly with urinary acidifying agents, resulting in lower serum concentrations.
- sarecycline
sodium acid phosphate will decrease the level or effect of sarecycline by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Multivalent cation-containing products may impair absorption of tetracyclines, which may decrease its efficacy. Separate dosing of tetracyclines from these products.
Minor (0)
Adverse Effects
Frequency Not Defined
Confusion
Dizziness
Gastrointestinal (GI) upset
Headache
Low urine output
Lower-extremity swelling
Mild laxative effect
Numbness or tingling
Shortness of breath
Tachycardia
Thirst
Weakness or heaviness of legs
Weight gain
Warnings
Contraindications
Patients with infected phosphate stones
Severe renal impairment
Hyperphosphatemia
Cautions
Patient may experience a mild laxative effect within first few days of therapy; if laxative effect persists, reduce the dose or discontinue use until diarrhea improves
Use caution in cardiac disease, especially in digitalized patients with heart failure, patients with hypertension, renal calculi, renal impairment, rickets, adrenal insufficiency, acute dehydration, renal disease, extensive tissue breakdown, as in severe burns, myotonia congenita, cirrhosis of liver, edema, hypertension, hypoparathyroidism, acute pancreatitis, hepatic impairment, hypernatremia, metabolic alkalosis
Pregnancy & Lactation
Pregnancy category: C
Lactation: Unknown whether drug is distributed in breast milk; caution is advised
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.Pharmacology
Mechanism of Action
Acidifies urine; essential in physiologic processes
Elimination
Excretion: Kidney
Administration
Oral Administration
Take with full glass of water
Avoid antacids containing aluminum, magnesium, or calcium
May precipitate passage of existing kidney stones
Images
Formulary
Adding plans allows you to compare formulary status to other drugs in the same class.
To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.
Adding plans allows you to:
- View the formulary and any restrictions for each plan.
- Manage and view all your plans together – even plans in different states.
- Compare formulary status to other drugs in the same class.
- Access your plan list on any device – mobile or desktop.
