A lancet assembly comprises a housing and a needle carriage movably housed within the housing, the needle carriage adapted to support a needle thereon, the needle carriage having a first end and a second end generally opposite thereto. A needle is mounted to the needle carriage and a guide element is positioned within the housing for guiding the needle carriage for reciprocating translation. A pivotal drive cam is provided for driving the needle carriage in translation and has a cam lobe for engaging the second end of the needle carriage, wherein the needle carriage is guided by the guide element and driven in translation by the pivotal drive cam such that the guidance and drive are kept separate. The pivotal drive cam can be moved between a cocked, retracted position, a fired, retracted position, and an extended position in between the cocked retracted position and the fired, retracted position. The lancet assembly can include a guidance biasing spring for biasing the needle carriage toward a retracted position and a separate drive spring for storing potential energy for pivoting the pivotal drive cam.
