Absorption, Distribution and Excretion
Tmax for phosphate absorption with orally administered liquid sodium phosphate is 1-3h.
... Phosphates (dibasic and monobasic sodium phosphate) are slowly and incompletely absorbed. /Dibasic and Monobasic Sodium phosphate/
Net phosphorus absorption may occur in the small intestine in some species but is primarily a function of the colon in horses. /Phosphorus/
Elimination: Renal (90%) and fecal (10%). /Phosphates/
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. /Phosphates/
For more Absorption, Distribution and Excretion (Complete) data for DISODIUM HYDROGEN PHOSPHATE (9 total), please visit the HSDB record page.

Interactions
Except for D-thyroxine, the hypocholesterolemic agents tested did not prevent the formation of cardiac lesions in rats on a thrombogenic diet, being treated with large doses of disodium phosphate.
Disodium phosphate increased the antirachitic activity of vitamin D3 in 3 week old rats.
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/
For more Interactions (Complete) data for DISODIUM HYDROGEN PHOSPHATE (8 total), please visit the HSDB record page.

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Non-Human Toxicity Values
LD50 Rat oral 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.

Sodium phosphate, dibasic appears as a colorless to white crystalline solid. Soluble in water. The primary hazard is the threat to the environment. Immediate steps should be taken to limit spread to the environment. Used as a fertilizer, in pharmaceuticals, in food processing, and for many other uses.
Disodium hydrogenphosphate is a sodium phosphate.

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Drug Indication
Used to treat constipation or to clean the bowel before a colonoscopy.

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Mechanism of Action
Sodium phosphate is thought to work by increasing the amount of solute present in the intestinal lumen thereby creating an osmotic gradient which draws water into the lumen.
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/

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Therapeutic Uses
Cathartics
Sodium Phosphates Injection, USP, ... 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 parenteral fluid formulas when the needs of the patient cannot be met by standard electrolyte or nutrient solutions. /Included in US product label/
Visicol tablets are indicated for cleansing of the colon as a preparation for colonoscopy in adults 18 years of age or older. /Included in US product label/
Although sodium and/or potassium phosphates have been used in the treatment of hypercalcemia, USP medical advisory panels do not recommend this use since these medications have been replaced by safer and more effective agents. /Phosphates/
For more Therapeutic Uses (Complete) data for DISODIUM HYDROGEN PHOSPHATE (14 total), please visit the HSDB record page.

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Drug Warnings
/BOXED WARNING/ There have been rare, but serious reports of acute phosphate nephropathy in patients who received oral sodium phosphate products for colon cleansing prior to colonoscopy. Some cases have resulted in permanent impairment of renal function and some patients required long-term dialysis. While some cases have occurred in patients without identifiable risk factors, patients at increased risk of acute phosphate nephropathy may include those with increased age, hypovolemia, increased bowel transit time (such as bowel obstruction), active colitis, or baseline kidney disease, and those using medicines that affect renal perfusion or function (such as diuretics, angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and possibly nonsteroidal anti-inflammatory drugs (NSAIDs)).
FDA has become aware of reports of acute phosphate nephropathy, a type of acute kidney injury, associated with the use of oral sodium phosphate products (OSP) for bowel cleansing prior to colonoscopy or other procedures. These products include the prescription products, Visicol and OsmoPrep, and OSPs available over-the-counter without a prescription as laxatives (e.g., Fleet Phospho-soda). In some cases when used for bowel cleansing, these serious adverse events have occurred in patients without identifiable factors that would put them at risk for developing acute kidney injury. We cannot rule out, however, that some of these patients were dehydrated prior to ingestion of OSPs or they did not drink sufficient fluids after ingesting OSP. Acute phosphate nephropathy is a form of acute kidney injury that is associated with deposits of calcium-phosphate crystals in the renal tubules that may result in permanent renal function impairment. Acute phosphate nephropathy is a rare, serious adverse event that has been associated with the use of OSPs. The occurrence of these events was previously described in an Information for Healthcare Professionals sheet and an FDA Science Paper issued in May 2006. Additional cases of acute phosphate nephropathy have been reported to FDA and described in the literature since these were issued. Individuals who appear to have an increased risk of acute phosphate nephropathy following the use of OSPs include persons: who are over age 55; who are hypovolemic or have decreased intravascular volume; who have baseline kidney disease, bowel obstruction, or active colitis; and who are using medications that affect renal perfusion or function (such as diuretics, angiotensin converting enzyme [ACE] inhibitors, angiotensin receptor blockers [ARBs], and possibly nonsteroidal anti-inflammatory drugs [NSAIDs]). As a result of new safety information received, FDA is requiring the manufacturer of Visicol and OsmoPrep, the two OSPs available by prescription only, to add a Boxed Warning to the labeling for these products. FDA is also requiring that the manufacturer develop and implement a risk evaluation and mitigation strategy (REMS), which will include a Medication Guide, to ensure that the benefits of these products outweigh the risk of acute phosphate nephropathy, and to conduct a postmarketing clinical trial to further assess the risk of acute kidney injury with use of these products.
This phosphate should not be confused with tribasic sodium phosphate which is very alkaline and has caustic action.
Oral administration is safer, but careful monitoring of serum electrolyte levels and renal function is necessary. Nausea, vomiting, and diarrhea may occur and may be dose dependent. Concomitant use of antacids containing aluminum and/or magnesium should be avoided, because they may bind phosphate and prevent it absorption (calcium antacids also may bind phosphate, and it is assumed that these agents are not given to hypercalcemic patients). /Monobasic or dibasic sodium or potassium phosphate/
For more Drug Warnings (Complete) data for DISODIUM HYDROGEN PHOSPHATE (57 total), please visit the HSDB record page.

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Pharmacodynamics
Sodium phosphate inceases fecal water content to increase mobility through the large intestine.

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.)