Azatadine is an antihistamine, which blocks the effects of the naturally occurring chemical histamine in the body. Azatadine is used to treat sneezing; runny nose; itching, watery eyes; hives; rashes; and other symptoms of allergies and the common cold. The antihistamines antagonize those pharmacological effects of histamine, which are mediated through activation of H1- receptor sites and thereby reduce the intensity of allergic reactions and tissue injury response involving histamine release.

Dimethyl maleate is an organic compound, the (Z)-isomer of the dimethyl ester of fumaric acid. Dimethyl maleate can be synthesized from maleic anhydride and methanol, with sulfuric acid acting as acid catalyst, via a nucleophilic acyl substitution for the monomethyl ester, followed by a Fischer esterification reaction for the dimethyl ester. Dimethyl maleate is used in many organic syntheses as a dienophile for diene synthesis. It is used as an additive and intermediate for plastics, pigments, pharmaceuticals, and agricultural products. It is also an intermediate for the production of paints, adhesives, and copolymers.

Azatadine is an antihistamine, which blocks the effects of the naturally occurring chemical histamine in the body. Azatadine is used to treat sneezing; runny nose; itching, watery eyes; hives; rashes; and other symptoms of allergies and the common cold. The antihistamines antagonize those pharmacological effects of histamine, which are mediated through activation of H1- receptor sites and thereby reduce the intensity of allergic reactions and tissue injury response involving histamine release.