Absorption, Distribution and Excretion
Potassium salts are well absorbed from the GI tract. Ingested phosphates are absorbed from the gastrointestinal tract. However, the presence of large amounts of calcium or aluminum may lead to formation of insoluble phosphate and reduce the net absorption. Vitamin D stimulates phosphate absorption.
Renal (90%) and fecal (10%) Phosphates Potassium is excreted mainly by the kidneys. Small amounts of potassium may be excreted via the skin and intestinal tract, but most of the potassium excreted into the intestine is later reabsorbed.
Potassium first enters the extracellular fluid and is then actively transported into the cells where its concentration is up to 40 times that outside the cell. Dextrose, insulin, and oxygen facilitate movement of potassium into cells.
Phosphates are rapidly cleared by dialysis. Dialysis can also be used to treat other electrolyte abnormalities such as hypernatremia, hypocalcemia, and hypomagnesemia.
Intravenously infused phosphorus not taken up by the tissues is excreted almost entirely in the urine.
Potassium salts are well absorbed from the GI tract. ... Potassium first enters the extracellular fluid and is then actively transported into the cells where its concentration is up to 40 times that outside the cell. Dextrose, insulin, and oxygen facilitate movement of potassium into cells. In healthy adults, plasma potassium concentrations generally range from 3.5-5 mEq/L. Plasma concentrations up to 7.7 mEq/L may be normal in neonates. ... Potassium is excreted mainly by the kidneys. The cation is filtered by the glomeruli, reabsorbed in the proximal tubule, and secreted in the distal tubule, the site of sodium-potassium exchange. Tubular secretion of potassium is also influenced by chloride ion concentration, hydrogen ion exchange, acid-base equilibrium, and adrenal hormones. Healthy patients on potassium-free diets usually excrete 40-50 mEq of potassium daily. ... Small amounts of potassium may be excreted via the skin and intestinal tract, but most of the potassium excreted into the intestine is later reabsorbed. /Potassium Supplements/
More than 90% of plasma phosphate is freely filtered at the glomerulus, and 80% is actively reabsorbed, predominatly in the initial segment of the proximal convoluted tubule but also in th e proximal straight tubule (pars recta). ... Parathyroid hormone (PTH) increases urinary phosphate excretion by blocking phosphate absorption. Expansion of plasma volume increases urinary phosphate excretion. /Phosphate/
Transport of phosphate from the intestinal lumen is an active, energy-dependent process ... In adults, about two-thirds of the ingested phosphate is absorbed and is excreted almost entirely into the urine. In growing children, phosphate balance is positive, and plasma concentrations of phosphate in plasma are higher in children than in adults. /Phosphates/
For more Absorption, Distribution and Excretion (Complete) data for MONOPOTASSIUM DIHYDROGEN PHOSPHATE (6 total), please visit the HSDB record page.

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Biological Half-Life
In healthy children with phosphate overdose, half-life was 4.8 to 10.6 hours, and was prolonged to 17 hours in a child with renal insufficiency.

Protein Binding
In healthy adults, plasma potassium concentrations generally range from 3.5-5 mEq/L. Plasma concentrations up to 7.7 mEq/L may be normal in neonates.

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Interactions
Potassium supplements should not be administered to patients receiving potassium-sparing drugs such as amiloride, spironolactone, and triamterene. /Potassium Supplements/
Concurrent use with potassium and sodium phosphates combination or monobasic potassium phosphate may increase plasma concentrations of salicylates since salicylate excretion is decreased in acidified urine; addition of these phosphates to patients stabilized on a salicylate may lead to toxic salicylate concentrations.
Concurrent use with foods or medicines containing phosphates will decrease iron absorption because of the formation of less soluble or insoluble complexes; iron supplements should not be taken within 1 hour before or 2 hours after ingestion of phosphates. /Phosphates/
Use of potassium phosphates injection in digitalized patients with severe or complete heart block is not recommended because of possible hyperkalemia. /Phosphates/
For more Interactions (Complete) data for MONOPOTASSIUM DIHYDROGEN PHOSPHATE (8 total), please visit the HSDB record page.

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Non-Human Toxicity Values
LD50 Mouse oral 2820 mg/kg bw
LD50 Rat oral 3200 mg/kg bw
LD50 Mouse oral about 1700 mg/kg bw

Potassium dihydrogen phosphate is a potassium salt in which dihydrogen phosphate(1-) is the counterion. It has a role as a fertilizer. It is a potassium salt and an inorganic phosphate.
Monopotassium phosphate, MKP, (also potassium dihydrogenphosphate, KDP, or monobasic potassium phosphate), KH2PO4, is a soluble salt of potassium and the dihydrogen phosphate ion. It is a source of phosphorus and potassium as well as a buffering agent. It can be used in fertilizer mixtures to reduce escape of ammonia by keeping pH low.

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Drug Indication
Used in buffers (determination of pH, pharmaceutical production, urinary acidifier, paper processing, baking powder, and food), nutrient solutions, yeast foods, special liquid fertilizers, sonar systems and other electronic applications; Used as a nutritional supplement in foods, a nonlinear optical material for laser use, and in wastewater treatment;

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Mechanism of Action
hosphorus has a number of important functions in the biochemistry of the body. The bulk of the body's phosphorus is located in the bones, where it plays a key role in osteoblastic and osteoclastic activities. Enzymatically catalyzed phosphate-transfer reactions are numerous and vital in the metabolism of carbohydrate, lipid and protein, and a proper concentration of the anion is of primary importance in assuring an orderly biochemical sequence. ln addition, phosphorus plays an important role in modifying steady-state tissue concentrations of calcium. Phosphate ions are important buffers of the intracellular fluid, and also play a primary role in the renal excretion of the hydrogen ion. Oral administration of inorganic phosphates increases serum phosphate levels. Phosphates lower urinary calcium levels in idiopathic hypercalciuria.

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Therapeutic Uses
The solution is intended to provide phosphate ion, (PO4-3) for addition to large volume infusion fluids for intravenous use. Potassium Phosphates Injection, USP, 3 mM P/mL, is indicated as a source of phosphorus, for addition to large volume intravenous fluids, to prevent or correct hypophosphatemia in patients with restricted or no oral intake. It is also useful as an additive for preparing specific intravenous fluid formulas when the needs of the patient cannot be met by standard electrolyte or nutrient solutions. The concomitant amount of potassium (4.4 mEq/mL) must be calculated into total electrolyte content of such prepared solutions.
Urinary acidification by potassium and sodium phosphates combination and monobasic potassium phosphate augments the efficacy of methenamine mandelate and methenamine hippurate, which are dependent upon an acid medium for antibacterial activity. Phosphates eliminate the odor, rash, and turbidity present with ammoniacal urine associated with urinary tract infections. However, use of phosphates for urea splitting urinary tract infections may predispose to struvite stones that form in alkaline urine. /Included in US product labeling/
Potassium and sodium phosphates combination and monobasic potassium phosphate have been used to reduce urinary calcium concentration and help prevent precipitation of calcium deposits in the urinary tract. /Included in US product labeling/
At the renal distal tubule, the secretion of hydrogen by the tubular cell in exchange for sodium in the tubular urine converts dibasic phosphate salts to monobasic phosphate salts. Therefore, large amounts of acid can be excreted without lowering the pH of the urine to a degree that would block hydrogen transport by a high concentration gradient between the tubular cell and luminal fluid. /Phosphates/
For more Therapeutic Uses (Complete) data for MONOPOTASSIUM DIHYDROGEN PHOSPHATE (7 total), please visit the HSDB record page.

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Drug Warnings
Potassium Phosphates Injection is contraindicated in diseases where high potassium, high phosphorus or low calcium levels may be encountered.
Hypophosphatemia should be avoided during periods of total parenteral nutrition, or other lengthy periods of intravenous infusions. Serum phosphorus levels should be regularly monitored, and appropriate amounts of phosphorus should be added to the infusions to maintain normal serum phosphorus levels. Intravenous infusion of inorganic phosphorus may be accompanied by a decrease in the serum level and urinary excretion of calcium. The normal level of serum inorganic phosphorus is 3.0 to 4.5 mg/dL in adults and 4.0 to 7.0 mg/dL in children.
To avoid potassium or phosphorus intoxication, infuse solutions containing potassium phosphates slowly. In patients with severe renal or adrenal insufficiency, administration of Potassium Phosphates Injection may cause potassium intoxication. Infusing high concentrations of phosphorus may cause hypocalcemia, and calcium levels should be monitored.
Solutions which contain potassium ions should be used with great care if at all, in patients with hyperkalemia, severe renal failure and in conditions in which potassium retention is present.
For more Drug Warnings (Complete) data for MONOPOTASSIUM DIHYDROGEN PHOSPHATE (16 total), please visit the HSDB record page.

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Pharmacodynamics
Potassium is the major cation of intracellular fluid and is essential for maintenance of acid-base balance, isotonicity, and electrodynamic characteristics of the cell. Potassium is an important activator in many enzymatic reactions and is essential to a number of physiologic processes including transmission of nerve impulses; contraction of cardiac, smooth, and skeletal muscles; gastric secretion; renal function; tissue synthesis; and carbohydrate metabolism. Phosphate is a major intracellular anion that participates in providing energy for metabolism of substrates and contributes to important metabolic and enzymatic reactions in almost all organs and tissues. Phosphate exerts a modifying influence on calcium concentrations, a buffering effect on acid-base equilibrium, and has a major 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.)