Emedastine Difumarate and its Impurities

Emedastine Difumarate (trade name Emadine) is a second generation antihistamine used in eye drops to alleviate the symptoms of allergic conjunctivitis. Reference standards of Emedastine Difumarate API, and its pharmacopeial, non pharmacopeial impurities, and stable isotopes are listed below.