Papular urticaria is a common disorder occurring due to a hypersensitivity reaction secondary to bites of insects such as mosquitoes, bed bugs, fleas and ticks. It usually presents as pruritic recurrent papules or vesicles with different degrees of surrounding edema¹ and a central punctum. It has been updated earlier that papular urticaria is an early marker of atopic march. In this article we review the possible cascade of events by which papular urticaria (Insect bite reaction) could trigger the cascade of events leading to atopic diathesis.