Absorption, Distribution and Excretion
Potassium salts are well absorbed in the gastrointestinal tract. Ingested phosphates are also absorbed in the gastrointestinal tract. However, the presence of large amounts of calcium or aluminum may lead to the formation of insoluble phosphates, thus reducing net absorption. Vitamin D promotes phosphate absorption.
Kidney (90%) and Fecal (10%) Excretion of potassium phosphate is primarily through the kidneys. Small amounts of potassium may be excreted through the skin and intestines, but most of the potassium excreted into the intestines is subsequently reabsorbed.
Potassium first enters the extracellular fluid and is then actively transported into cells, where the concentration can be up to 40 times higher than extracellular. Glucose, insulin, and oxygen promote potassium entry into cells.
Phosphate can be rapidly removed by dialysis. Dialysis can also be used to treat other electrolyte disturbances such as hypernatremia, hypocalcemia, and hypomagnesemia.
Intravenously infused phosphorus is almost entirely excreted in the urine after not being absorbed by tissues.
Potassium salts are readily absorbed from the gastrointestinal tract. Potassium first enters the extracellular fluid and is then actively transported into the cells, where its concentration can be up to 40 times higher than extracellular. Glucose, insulin, and oxygen promote potassium entry into cells. The plasma potassium concentration in healthy adults is typically between 3.5 and 5 mEq/L. Neonatal plasma potassium concentrations as high as 7.7 mEq/L may be within the normal range. Potassium is primarily excreted through the kidneys. Potassium ions are filtered by the glomeruli, reabsorbed in the proximal tubules, and secreted in the distal tubules (sites of sodium-potassium exchange). Renal tubular potassium secretion is also influenced by chloride ion concentration, hydrogen ion exchange, acid-base balance, and adrenal hormones. Even without potassium intake, healthy individuals typically excrete 40-50 mEq of potassium daily. A small amount of potassium may be excreted through the skin and intestines, but most of the potassium excreted into the intestines is subsequently reabsorbed. /Potassium Supplements/
Over 90% of plasma phosphate is freely filtered at the glomerulus, and 80% is actively reabsorbed, primarily in the initial segment of the proximal tubule, but also in the proximal straight tubule (straight segment). ... Parathyroid hormone (PTH) increases urinary phosphate excretion by inhibiting phosphate absorption. Plasma volume expansion also increases urinary phosphate excretion. /Phosphate/
Phosphate transport from the intestinal lumen is an active, energy-dependent process... In adults, approximately two-thirds of ingested phosphate is absorbed and almost entirely excreted in the urine. In growing children, the phosphate balance is positive, and plasma phosphate concentrations are higher in children than in adults. /Phosphate/
For more complete data on the absorption, distribution, and excretion of potassium dihydrogen phosphate (6 types), please visit the HSDB record page.

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Biological half-life
In healthy children, the half-life of phosphate in excess is 4.8 to 10.6 hours, while in children with renal insufficiency, the half-life is extended to 17 hours.

Protein Binding
In healthy adults, plasma potassium concentrations are typically between 3.5 and 5 mEq/L. Neonatal plasma potassium concentrations as high as 7.7 mEq/L may be within the normal range. Interactions Patients taking potassium-sparing medications (such as amiloride, spironolactone, and triamterene) should not take potassium supplements. /Potassium Supplements/
Concomitant use of potassium sodium phosphate or potassium dihydrogen phosphate may increase plasma salicylate concentrations because acidification of urine reduces salicylate excretion; in patients already taking salicylate and whose condition is stable, adding these phosphates may result in excessively high salicylate concentrations, reaching toxic levels.
Concomitant consumption of phosphate-containing foods or medications may reduce iron absorption due to the formation of poorly soluble or insoluble complexes; iron supplements should not be taken within one hour before or after taking phosphates. /Phosphate/
Due to the potential for hyperkalemia, potassium phosphate injections are not recommended for patients receiving digitalis treatment with severe or complete atrioventricular block. /Phosphate/
For more complete data on interactions of potassium dihydrogen phosphate (8 types), please visit the HSDB record page.

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Non-human toxicity values
Mice oral LD50: 2820 mg/kg body weight
Rat oral LD50: 3200 mg/kg body weight
Mice oral LD50: Approximately 1700 mg/kg body weight

Potassium dihydrogen phosphate (KH2PO4) is a potassium salt in which the dihydrogen phosphate ion (1-) is a counterion. It is a fertilizer. It is a potassium salt and also an inorganic phosphate. KH2PO4, also known as potassium dihydrogen phosphate, KDP, or monobasic potassium phosphate, is a soluble salt of potassium and dihydrogen phosphate ions. It is a source of phosphorus and potassium and also a buffer. It can be used in fertilizer mixtures to reduce ammonia escaping by maintaining a lower pH. Pharmaceutical Indications: Used as a buffer (pH measurement, pharmaceutical production, urine acidifier, paper processing, baking powder and food), nutrient solution, yeast food, special liquid fertilizer, sonar systems and other electronic applications; phosphorus can be used as a nutritional supplement in food, a nonlinear optical material for lasers, and a wastewater treatment agent; Mechanism of Action: Phosphorus has many important functions in human biochemistry. Most of the phosphorus in the human body is found in bones, playing a key role in the activity of osteoblasts and osteoclasts. Enzymatic phosphate transfer reactions are numerous and crucial in the metabolism of carbohydrates, lipids, and proteins, and appropriate phosphate anion concentrations are essential for ensuring orderly biochemical processes. Furthermore, phosphorus plays a vital role in regulating calcium homeostasis in tissues. Phosphate ions are important buffers in intracellular fluid and also play a major role in the renal excretion of hydrogen ions. Oral administration of inorganic phosphates can increase serum phosphate levels. Phosphates can reduce urinary calcium levels in patients with idiopathic hypercalciuria.

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Therapeutic Use
This solution is intended to provide phosphate ions (PO4-3) for addition to large-volume intravenous infusions. Potassium phosphate injection (USP, 3 mMP/mL) can be used as a phosphorus source added to large-volume intravenous infusions to prevent or correct hypophosphatemia in patients with limited or no oral intake. This product can also be used as an additive in the formulation of specific intravenous infusion solutions when standard electrolytes or nutritional solutions cannot meet the patient's needs. The accompanying potassium content (4.4 mEq/mL) must be included in the total electrolyte content of such formulations.
Acidifying urine with potassium sodium phosphate mixtures and potassium dihydrogen phosphate enhances the efficacy of methylammonium mandelate and methylammonium hippurate, both of which have antibacterial activity dependent on an acidic environment. Phosphates eliminate the odor, rash, and turbidity of ammonia-induced urinary tract infections. However, using phosphates to treat urea-degrading urinary tract infections may increase the risk of struvite formation in alkaline urine. /US product label contains/
Potassium sodium phosphate mixtures and potassium dihydrogen phosphate have been used to lower urinary calcium concentrations and help prevent calcium deposition in the urinary tract. /US product label contains/
In the distal convoluted tubule of the kidney, tubular cells secrete hydrogen ions to exchange with sodium ions in the urine, converting hydrogen phosphate to dihydrogen phosphate. Therefore, a large amount of acid can be excreted without lowering the urine pH to a level sufficient to impede the transport of high concentration gradient hydrogen ions between the tubular cells and the tubular fluid. /Phosphates/
For more complete data on the therapeutic uses of potassium dihydrogen phosphate (7 types), please visit the HSDB record page. Drug Warnings Potassium phosphate injection is contraindicated in patients with hyperkalemia, hyperphosphatemia, or hypocalcemia. Hypophosphatemia should be avoided during total parenteral nutrition or other prolonged intravenous infusions. Serum phosphorus levels should be monitored regularly, and appropriate amounts of phosphorus should be added to the infusion as needed to maintain normal serum phosphorus levels. Intravenous infusion of inorganic phosphorus may lead to decreased serum calcium levels and increased urinary calcium excretion. Normal serum inorganic phosphorus levels are 3.0 to 4.5 mg/dL in adults and 4.0 to 7.0 mg/dL in children. To avoid potassium or phosphorus toxicity, potassium phosphate solutions should be infused slowly. Potassium phosphate injection may cause potassium toxicity in patients with severe renal or adrenal insufficiency. Infusion of high concentrations of phosphorus may cause hypocalcemia; calcium levels should be monitored. Potassium-containing solutions should be used with caution, or even avoided altogether, in patients with hyperkalemia, severe renal failure, or potassium retention. For more complete data on drug warnings regarding potassium dihydrogen phosphate (16 in total), please visit the HSDB record page.

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Pharmacodynamics
Potassium is the main cation in intracellular fluid and is essential for maintaining cellular acid-base balance, isotonicity, and electrodynamic properties. Potassium is an important activator of many enzymatic reactions and is indispensable for a variety of physiological processes, including nerve impulse transmission; contraction of cardiac, smooth, and skeletal muscles; gastric juice secretion; renal function; tissue synthesis; and carbohydrate metabolism. Phosphate is the main intracellular anion, participating in providing energy for substrate metabolism and participating in important metabolic and enzymatic reactions in almost all organs and tissues. Phosphate plays a regulatory role in calcium ion concentration, a buffering role in acid-base balance, and an important role in the renal excretion of hydrogen ions.

H2KO4P

136.0855

135.932

7778-77-0

Phosphate monobasic-d2 potassium;13761-79-0

516951

Colorless crystals or white granular powder
White tetragonal crystals

2.338

158ºC at 760 mmHg

252.6ºC

2

4

0

6

61.9

0

[K+].P(=O)(O[H])(O[H])[O-]

GNSKLFRGEWLPPA-UHFFFAOYSA-M

InChI=1S/K.H3O4P/c;1-5(2,3)4/h;(H3,1,2,3,4)/q+1;/p-1

potassium;dihydrogen phosphate

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

H2O : ~50 mg/mL (~367.40 mM)
DMSO :< 1 mg/mL

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)