Summary
Dexamethasone 21-phosphate disodium salt is a system glucocorticoid with anti-inflammatory properties, is the pro-drug which is converted to dexamethasone in vivo. It stimulates uptake of glutamine in the cerebral cortex and induces apoptosis. In addition to binding to specific nuclear steroid receptors, dexamethasone also interferes with NF-kB activation and apoptotic pathways.
It is freely soluble in water, slightly soluble in ethanol, and insoluble in chloroform and in ether. It is an inhibitor of the sodium phosphate symporter and GR activator.
Additionally, it serves as an activator of food, medicine, glucocorticoid and anti inflammatory.
Anti-inflammatory drugs
Dexamethasone sodium phosphate (DSP), chemical name 16a-methyl-11β,17a,21-trihydroxy-9a-fluoropregna-1,4-diene-3,20-dione-21-Phosphate disodium salt, belongs to the adrenal cortex hormones. It has the effect of antiphlogosis by stabilizing the lysosomal membrane, reducing the release of lysosomal hydrolase; inhibiting the formation of inflammation-induced material bradykinin, serotonin and prostaglandin, increasing the stability of mast cells particles, reducing the release of histamine, concentrate blood vessels, stop white blood cells and macrophages from migrating outside of the blood vessels, etc. It can inhibit macrophage function to play immunization function and inhibit the formation of fibroblasts which is conducive to prevent corneal scar. When used for trauma, it can stop scar from forming and protect eyesight. It can inhibit or reduce the formation of new vessel in the cornea and conjunctiva disease and alleviate rejection reaction and scar formation in local use. In clinical treatment it can be used for autoimmune diseases, allergies, inflammation, rheumatism, asthma, ophthalmology and dermatology and other diseases.
Characteristic
This product is white or off-white powder; odorless with slightly bitter taste and hygroscopicity. It can dissolve in water or methanol but is almost insoluble in acetone or ether. Melting point 233-235 ℃.
Pharmacology effect
This product can relieve and prevent the reaction of organization to inflammation. In the early stage of acute inflammation, it can reduce the exudation of local edema by inhibiting capillary permeability, leukocyte infiltration and phagocytosis and reducing the release of various inflammatory mediators In the late inflammatory phase, it can inhibit capillary and fibroblast proliferation and collagen protein synthesis to prevent adhesion and scar formation.
- Immunity inhibition and anti-allergic effects
This product can prevent or inhibit cell-mediated immune response, delayed allergic reactions,reduce the number of T lymphocytes, monocytes and brucella cells, reduce the integration ability between immunoglobulin and cell surface receptors and inhibit interleukin synthesis and release, thus inhibting the transformation of T lymphocytes to lymphocyte and pathological changes caused by allergic reactions such as allergic congestion, edema, exudation, rash, smooth muscle spasm, cell damage. and so on. This product also prevents the immune replenishment from getting through the basement membrane and can reduce the complement component and immunoglobulin concentration. In addition it can inhibit the transplant rejection reaction of tissue and organ and has certain short-term effect on autoimmune diseases.
- The treatment effect on ophthalmic diseases
Inhibition of corneal epithelial regeneration, in the cornea, conjunctival disease can inhibit or reduce the formation of new blood vessels.
Pharmacokinetics
This product is adrenal corticosteroid drugs. Its effect is similar to hydrocortisone but stronger with anti-inflammatory effect 40-50 times that of hydrocortisone and more notable effect of anti-inflammatory, anti-allergy, anti-shock than prednisone. It has quick efficacy and less side effects improving the body function in short time especially for the forst aid in critical illnesses.
This product affects sugar metabolism and has strong function of anti-inflammatory, anti-inflammatory, anti-inflammatory and anti-allergy It affects water and sodium retention slightly and has strong inhibitory effect on pituitary-adrenal so it just causes slight side effects such as edema, hypertension,muscle weakness and so on. This product transpires through kidneys in urine after metabolic transformation in liver so the drug's plasma half-life can extend for people with liver and renal dysfunction.
The concentration reaches plasma peak one hour after intramuscular and plasma protein binding rate is lower than other corticosteroids drug.
Adverse Reaction
- The main adverse reactions of this product is concurrent infection, including fungi, tuberculosis, staphylococcus, proteus, pseudomonas aeruginosa and a variety of herpes virus
- Long-term use can cause iatrogenic Cushing's syndrome.
- For patients suffering from chronic wasting disease or mental disorders before, such mental symptoms may occur:euphoria, excitement, delirium, anxiety, orientation disorder or inhibition.
- Some patients with long-term local drug use may suffer hormone glaucoma and hormone cataracts.
- Glucocorticoid withdrawal syndrome. Sometimes the patient stop taking medicine may suffer dizziness, fainting tendencies, abdominal pain or back pain, fever, loss of appetite, nausea, vomiting, muscle or joint pain, headache, fatigue, weakness, which can be considered to be glucocorticoid-dependent syndrome adrenal insufficiency and the recurrence of original disease are excluded after careful examination.
Medicine interactions
- The decomposition of this product can be speeded and metabolic promotion is weakened if taken with barbiturates, phenytoin, rifampicin and other liver enzyme inducer
- The toxicity increases combined with salicylic acid
- The product can reduce the effect of anticoagulant and oral hypoglycemic and attention should be paid adjust the dose.
- Incompatible with hydrochloric vancomycin
Precautions
- Patients with tuberculosis, acute bacterial or viral infections must be given appropriate anti-infective treatment.
- For eye infections combined with effective antibiotics. Patients with
- corneal ulcers are not permitted. When patient’s condition turns better dose times should be gradually reduced in case of recurrence.
- Patients with diabetes, osteoporosis, cirrhosis, renal dysfunction, and hypothyroidism should be cautious to take.
- After long-term medication, dosage should be gradually reduced before stop.
- Athletes with caution.
Special people medication
- Pregnant women and lactatinal women medication
This product with teratogenic effect in animal test can increase the probability of placental insufficiency, neonatal weight loss or stillbirth. So the pregnant women should weight advantages and disadvantages before taking it. Nannie receiving high-dose administration should not breast feed, in case of drug transpiring through milk resulting in infant growth inhibition, adrenal function inefficiency and other adverse reactions
Be careful in giving infant adrental cortex hormones administration because it can inhibit infant from growth and development. If long-term use is necessary, short-acting or medium-acting agents should be used instead of long-acting dexamethasone preparations and changes in intracranial pressure should be observed.
Easy to suffer high blood pressure and diabetes. For old patients especially after-menopaue women the osteoporosis.tends to be severer.
Medication contraindication
Patients with allergic history to this product and adrenal corticosteroids should not be permitted and in special case pros and cons should be weighed before use .Pay attention to the deterioration of the disease: It is not suitable for patients with hypertension, thrombosis, stomach and duodenal ulcer, psychosis, electrolyte metabolism, myocardial infarction , visceral surgery, glaucoma and so on.
Dosage
Eye drops: dexamethasone sodium phosphate eye drops, 5ml: 1.25mg.
Injection: dexamethasone sodium phosphate injection, 1ml: 5mg, 1ml: 2mg.
Dexamethasone sodium phosphate for injection, 10mg (based on dexamethasone sodium phosphate).
New formulation: dexamethasone sodium phosphate temperature-sensitive in situ gel.
Figure 1 is dexamethasone sodium phosphate injection
Storage
Away from light. Sealed. Stored in dry place at 4℃
Usage
- Adrenal corticosteroids drug, anti-inflammatory, anti-toxity, anti-allergy;
- An anti-excitment glucocorticoid and also a precursor drug that can be converted into dexamethasone in body stimulating glutamate to be absorbed into the cerebral cortex. It is used as adrenal corticosteroids clinically with anti-inflammatory, anti-drug and anti-allergy effect.
References
https://www.alfa.com/zh-cn/catalog/J64083/
http://www.tcichemicals.com/eshop/en/jp/commodity/D4438/
https://www.goldbio.com/product/4827/dexamethasone-21-phosphate-disodium-salt
Chemical Properties
White or almost white, very hygroscopic powder.
Originator
Decadron
Phosphate,MS and D,US,1959
Uses
Dexamethasone 21-phosphate disodium salt acts as an inducer of apoptosis and inhibitor of the sodium phosphate symporter. It is used in the treatment of emetic effects of cancer therapy and epicondylitis. Further, it serves as an activator of food, medicine, glucocorticoid and anti inflammatory.
Uses
Dexamethasone-21-phosphate disodium salt is used in eye and ear preparations and in systemic preparations.
Uses
glucocorticoid, antiinflammatory
Definition
ChEBI: An organic sodium salt which is the disodium salt of dexamethasone phosphate.
Manufacturing Process
A solution of bis-triethylamine phosphate was prepared by slowly adding 2.36
ml of 85% phosphoric acid to 20 ml of acetonitrile containing 9.9 ml of
triethylamine at 20°C. This solution was added to a stirred solution of 4.70 g
of 9α-fluoro-11β,17α,21-trihydroxy-16α-methyl-1,4-pregnadiene-3,2-dione 21-
methanesulfonate and 20 ml of acetonitrile. The mixture was heated under
reflux for four hours and then evaporated under reduced pressure to a volume
of 12 ml. This mixture was a concentrated solution of 9α-fluoro-11β,17α,21-
trihydroxy-16α-methyl-1,4-pregnadiene-3,20-dione 21-phosphate
triethylamine salt with some inorganic phosphate.
The mixture was cooled, 25 ml of methanol added, and the cooled mixture
treated with 33 ml of 1.89 N methanolic sodium methoxide solution. The
precipitated inorganic phosphates were removed by suction filtration and
washed thoroughly with methanol. The combined filtrates were evaporated
under reduced pressure to a volume of 12 ml and treated with 30 ml of
methanol. The resulting cloudy solution was clarified by filtration through
diatomaceous earth. The volume of the filtrate was brought to 40 ml by the
addition of methanol, and 120 ml of ether was added with stirring. The
precipitated product, which was 9α-fluoro-11β,17α,21-trihydroxy-16α-methyl1,4-pregnadiene-3,20-dione 21-phosphate sodium salt, was collected by
suction filtration, and washed with acetone and then with ether. The weight of
the air-dried material was 3.06 g.
brand name
Decadron (Merck); Dexacen (Cent); Dexacort (UCB); Dexair (Pharmafair); Hexadrol (Organon); Maxidex (Alcon).
Therapeutic Function
Glucocorticoid
Safety Profile
Poison by intravenous
route. Moderately toxic by ingestion and
intraperitoneal routes. Human systemic
effects by intravenous route: peritonitis,
central nervous system, and gastrointestinal
changes. An experimental teratogen. Other
experimental reproductive effects. When
heated to decomposition it emits toxic
fumes of F-, PO,, and Na2O.
