Absorption, Distribution and Excretion
Following oral administration of liquid sodium phosphate, the time to peak absorption (Tmax) of phosphate is 1–3 hours. …Phosphate (disodium hydrogen phosphate and sodium dihydrogen phosphate) absorption is slow and incomplete. /Disodium hydrogen phosphate and sodium dihydrogen phosphate/
In some animals, net phosphorus absorption may occur in the small intestine, but in horses, phosphorus absorption is primarily accomplished by the colon. /Phosphate/
Excretion routes: kidneys (90%) and feces (10%). /Phosphate/
Ingested phosphate is 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. /Phosphate/
For more complete data on the absorption, distribution, and excretion of disodium hydrogen phosphate (9 types), please visit the HSDB records page.

Interactions
Except for D-thyroxine, none of the cholesterol-lowering drugs tested prevented cardiac lesions in rats receiving a thrombotic diet and high doses of disodium hydrogen phosphate. Disodium hydrogen phosphate enhanced the anti-rickets activity of vitamin D3 in 3-week-old rats. Concomitant use with potassium and sodium phosphate complexes or potassium dihydrogen phosphate may increase plasma salicylate concentrations because acidification of urine reduces salicylate excretion; in patients already taking salicylate and in stable condition, adding these phosphates may result in excessively high salicylate concentrations, reaching toxic levels. Concomitant use with 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 1 hour before or 2 hours after taking phosphates. /Phosphates/ For more complete data on interactions of disodium hydrogen phosphate (8 types), please visit the HSDB records page.

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Non-human toxicity values
Oral LD50 in rats: 17 g/kg

[1]. Structure investigation on anhydrous disodium hydrogen phosphate using solid-state NMR and X-ray techniques. Journal of the American Chemical Society, 1995, 117(18): 5141-5147.

[2]. Pharmaceutical excipients - quality, regulatory and biopharmaceutical considerations. Eur J Pharm Sci. 2016 May 25;87:88-99.

Disodium hydrogen phosphate is a colorless to white crystalline solid, readily soluble in water. Its main hazard lies in its environmental threat. Immediate measures should be taken to limit its spread into the environment. Disodium hydrogen phosphate can be used as a fertilizer, pharmaceutical, food processing ingredient, and for many other purposes.
Disodium hydrogen phosphate is a type of sodium phosphate.
Pharmacological Indications

Used for the treatment of constipation or for bowel preparation before colonoscopy.
Mechanism of Action

The mechanism of action of sodium phosphate is believed to be to increase the solute content in the intestinal lumen, thereby creating an osmotic gradient that draws water into the intestinal lumen.
In the distal convoluted tubule of the kidney, renal tubular cells secrete hydrogen ions to exchange with sodium ions in the urine, converting disodium hydrogen phosphate to dihydrogen phosphate. Therefore, even with the excretion of large amounts of acid, the pH of the urine will not decrease to a level sufficient to impede the transport of the high concentration gradient of hydrogen between the renal tubular cells and the tubular fluid. /Phosphate/

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Therapeutic Use
Laxative
Sodium phosphate injection (USP)...is indicated as a phosphorus source to be added to large-volume intravenous infusions to prevent or correct hypophosphatemia in patients with limited or no oral intake. It may also be used as an additive in the formulation of specific parenteral nutrition solutions when standard electrolyte or nutritional solutions are insufficient for the patient's needs. /US Product Label Includes/
Visicol tablets are indicated for colon cleansing prior to colonoscopy in adults 18 years of age and older. /US Product Label Includes/
While sodium phosphate and/or potassium phosphate were once used to treat hypercalcemia, the United States Pharmacopeia (USP) Medical Advisory Panel does not recommend this use, as these medications have been superseded by safer and more effective alternatives. /Phosphate/
For more complete data on the therapeutic uses of disodium hydrogen phosphate (of 14 types), please visit the HSDB record page.

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Drug Warning
/Black Box Warning/ Rare but serious cases of acute phosphate nephropathy have been reported in patients who took oral sodium phosphate products for colon cleansing prior to colonoscopy. Some cases result in permanent kidney damage, and some patients require long-term dialysis. While some cases occur in patients without clear risk factors, high-risk groups for acute phosphate nephropathy may include: advanced age, hypovolemia, prolonged intestinal transit time (e.g., bowel obstruction), active colitis, or pre-existing kidney disease, as well as patients taking medications that affect renal perfusion or function (e.g., diuretics, angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and possibly nonsteroidal anti-inflammatory drugs (NSAIDs)). The U.S. Food and Drug Administration (FDA) has noted several reports of acute phosphate nephropathy (an acute kidney injury) associated with bowel cleansing using oral sodium phosphate products (OSPs) prior to colonoscopy or other examinations. These products include prescription drugs Visicol and OsmoPrep, as well as over-the-counter laxatives available without a prescription (e.g., Fleet Phospho-soda). In some cases, these serious adverse events have occurred in patients who did not have any identifiable risk factors for acute kidney injury when using oral rehydration salts (OSP) for bowel cleansing. However, we cannot rule out the possibility that some patients were already dehydrated before taking OSP or did not receive adequate hydration after taking OSP. Acute phosphate nephropathy is an acute kidney injury associated with the deposition of calcium phosphate crystals in the renal tubules, which can lead to permanent kidney damage. Acute phosphate nephropathy is a rare but serious adverse event associated with OSP use. These events were previously described in a Healthcare Practitioner Information Manual published by the U.S. Food and Drug Administration (FDA) in May 2006 and in a scientific document. Since the publication of these documents, the FDA has received more reports of acute phosphate nephropathy cases, and related descriptions have appeared in the literature. The risk of acute phosphate nephropathy may be increased in the following populations after using oral rehydration salts (OSP): those over 55 years of age; those with hypovolemia or reduced intravascular blood volume; those with underlying kidney disease, intestinal obstruction, or active colitis; and those taking medications that affect renal perfusion or function (e.g., diuretics, angiotensin-converting enzyme [ACE] inhibitors, angiotensin receptor blockers [ARBs], and possibly nonsteroidal anti-inflammatory drugs [NSAIDs]). In light of the new safety information received, the FDA has requested that the manufacturers of two prescription drugs—Visicol and OsmoPrep—add a boxed warning to their product labels. The FDA has also required manufacturers to develop and implement risk assessment and mitigation strategies (REMS), including guidelines for use, to ensure that the benefits of these products outweigh the risks of acute phosphate nephropathy, and to conduct post-marketing clinical trials to further assess the risk of acute kidney injury from using these products. This phosphate should not be confused with strongly alkaline and corrosive trisodium phosphate. Oral administration is safer, but serum electrolyte levels and renal function must be closely monitored. Nausea, vomiting, and diarrhea may occur and may be dose-related. Concomitant use of antacids containing aluminum and/or magnesium should be avoided, as they may bind to phosphates and prevent their absorption (calcium antacids may also bind to phosphates and are generally not used in patients with hypercalcemia). /Monophosphate or diphosphate sodium or potassium phosphate/
For more complete data on drug warnings for disodium hydrogen phosphate (57 in total), please visit the HSDB records page.

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Pharmacodynamics
Sodium phosphate increases the water content of stool, thereby increasing intestinal motility.

HNA2O4P

141.96

141.94

7558-79-4

Phosphate dibasic-d1 sodium;107632-22-4

24203

White to off-white solid powder

1.064 g/mL at 20 °C

158ºC at 760 mmHg

243-245 °C

1

4

0

7

46.5

0

BNIILDVGGAEEIG-UHFFFAOYSA-L

InChI=1S/2Na.H3O4P/c;;1-5(2,3)4/h;;(H3,1,2,3,4)/q2*+1;/p-2

disodium;hydrogen 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)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

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.)