METHOD AND APPARATUS FOR PIERCING THE SKIN AND DELIVERY OR COLLECTION OF LIQUIDS

The single use medical device includes a lancet piston slidingly and sealingly located in a bore of a lancet housing. The lancet piston operates as a positive displacement piston within the bore, allowing dispensing and/or aspiration of liquid into the bore. The lancet piston includes a sharp tip for pricking skin, and is particular applicability for allergen testing and blood or ISF sampling. The actuator device has an actuator member for releasable engagement with the lancet piston at a before-use position of the lancet piston via a clutch mechanism. The engagement of the actuator member with the lancet piston allows the actuator member to push/pull the lancet piston forwardly/rearwardly along the bore. At positions forward of the before-use position of the lancet piston, the engagement of the actuator member with the lancet piston is interlocked, assisting in the prevention of accidental needlestick injuries.