Brompheniramine Maleate is the maleate salt form of brompheniramine, an alkylamine derivative and a histamine antagonist with anticholinergic and sedative properties. Brompheniramine maleate competes with histamine for the H1 receptor. This diminishes the actions of histamine on effector cells and decreases the histamine-mediated symptoms of allergic reaction such as bronchoconstriction, vasodilation, increased capillary permeability and spasmodic contractions of gastrointestinal smooth muscle.