Dimetindine Maleate, an ingredient in Pediafast, blocks the effects of histamine, a chemical generated during allergic responses. It lowers swelling, eases itching and skin irritations brought on by allergic reactions, and eases the symptoms of allergic rhinitis, including sneezing, watery eyes, and a running nose. A dropper is included. It is antihistaminic, antipruritic, and antiallergic.