Allergic responses consist of :

1. Primary Responses (Primary Immune Responses). The immune response (cellular or humoral) to a first encounter with antigen . The primary response is generally small, has a long induction phase or lag period, consists primarily of IgM antibodies, and generates immunologic memory.

2. Secondary responses . The immune response which follows a second or subsequent encounter with a particular antigen. Can be severe in certain cases (e.g. Anaphylactic shock ).