An intradermal injection adapter (10) includes a body (16) having a longitudinal axis and a central portion (24) located distally relative to the body along the longitudinal axis (18). The central portion has a cannula channel therethrough extending generally parallel to the longitudinal axis. A cannula (14) within the cannula channel (26) has a sharpened tip (14a) for injection into a patient and a sharpened opposite proximal end for injection into a pen injector. A distal protrusion (30) has a first skin contacting surface (34) extending generally parallel to the longitudinal axis. The first skin contacting surface is spaced from the cannula such that a distal portion of the cannula extends generally parallel to the first skin contacting surface.