Name: Dexamethasone Sodium Phosphate BP.

T.S.No.: SPEC/API/ HDSP -019/B/01
Issue Date: 01/03/2006

Code: HDSP

CAS: 2392-39-4

Storage: Store in an airtight container, protected from light.

Supersede: SPEC/API/ HDSP-019/B

M.F.:  C22 H28 FNa2 O8P

M.W.: 516.40g/mole







A white or almost white powder; very hygroscopic. It shows polymorphism.



Freely soluble in water, slightly soluble in alcohol, practically insoluble in methylene chloride.



Test B and C OR Tests A,C,D,E and F.

Identification A        


The absorbance of the resulting solution at the maximum at about 419nm should not be less than 0.200 Abs.

Identification B       


The Infra-red absorption spectrum should be concordant with the reference spectrum of Dexamethasone sodium phosphate CRS.

Identification C      


The principal spot in the chromatogram obtained with the test solution should be similar, in position, colour in daylight, fluorescence in UV light at 365 nm and size to the principal spot in the chromatogram obtained with reference solution (a).The test should not valid unless the chromatogram obtained with reference solution (b) should show two spots which may, however, not be completely separated.

IIdentification D


The colour should fade and a clear solution should remain.

Identification E


The test solution should be yellow and the blank should be red.

Identification F


The solution should give the reaction (a) of sodium and reaction (b) of phosphate.

Appearance of solution


A 5% w/v solution in CO2 free water should be clear and not more intensely coloured than reference solution B7.



7.50 to 9.50 pH.

Specific optical rotation


+75.000 to  +83.000 on dried basis

Related substance  (By HPLC )


Any individual impurity: NMT 0.50%.

Any other impurity : NMT 1.00%

Inorganic phosphate


Not more than 1.00%w/w.



Not more Than 3.00%.

Ethanol and water


Not greater than 13.00%.



97.00% to 103.00%w/w on anhydrous basis & ethanol free substance.

End of specification