A self-sheathing injection assembly that includes a sheath protecting the medical professional from accidental punctures from the needle. The sheath is slidable to expose the end of the needle, and the sheath is lockable in the exposed condition with a detent mechanism. The separable needle assembly also includes features that firmly couples a carpule of medicine to the needle assembly, such that upon removal of the needle assembly after use the carpule remains attached to the needle for simultaneous disposal.

A cartridge comprising a reservoir part and an extension extending from said reservoir part, said extension defining a fluid path and comprising a molding and a first needle extending from said molding, the extension turning to a finite angle with respect to an axis of said reservoir part and wherein at least part of said first needle is likewise at said finite angle, at least some of said part of said first needle at said finite angle being enclosed within said molding of said fluid path.

A drug delivery device may be used with the cartridge and includes a skin-contacting surface. In use, the longitudinal axis of the interior of the cartridge may be disposed substantially parallel to the skin-contacting surface.

A disposable safety needle assembly and safety enclosure for internally shielding a used or contaminated needle includes a needle assembly having a needle cannula slidably disposed within a safety enclosure. An angular orientation to the needle within the enclosure maintains an insertion angle allowing the safety enclosure to remain substantially flush with a dermal surface during and while the needle is inserted. The safety enclosure also includes an internally disposed flexible safety member. The flexible safety member has face portion transversely situated and having a safety feature disposed to the needle and that slides thereon. Retracting the needle within the safety enclosure to a point wherein the sharp tip of the needle is beyond the needle protection section of the flexible member causes the protection section to travel transversely to the direction of motion of the needle. As a result, the safety feature receives the sharp tip of the needle.