azelastine and its Impurities
A histamine-H1-receptor antagonist, Azelastine is used in the treatment of rhinitis.It shows anti-histamine effect, mast-cell stabilizing effect and anti-inflammatory effect. Reference standards of Azelastine API, and its pharmacopeial, non pharmacopeial impurities, and stable isotopes are listed below.

![(R)-4-[(4-Chlorophenyl)methyl]-2-(hexahydro-1-meth PA 28 0591002](https://www.pharmaffiliates.com/pimages/PA280591002.jpg)
(R)-4-[(4-Chlorophenyl)methyl]-2-(hexahydro-1-methyl-1-oxido-1H-azepin-4-yl)-1(2H)-phthalazinone;
(R)-4-[(4-Chlorophenyl)methyl]-2-(hexahydro-1-methyl-1-oxido-1H-azepin-4-yl)-1(2H)-phthalazinone;
Catalogue No.:PA 28 0591002
CAS :
1346617-18-2
Molecular Formula : C22H24ClN3O2
Molecular Weight : 397.9