An apparatus (110) includes an activation mechanism (20) and a safety latch (122). The activation mechanism is operative to deploy a needle (116) to protrude out of a housing (112), the needle (116) having a longitudinal axis. The safety latch (122) is movably mounted on the housing (112) and formed with a needle opening (129) to allow the needle (116) to pass therethrough. The safety latch (122) has a first position wherein the needle (116) is aligned to pass through the needle opening (129) and a second position wherein the safety latch (122) is moved with respect to the housing (112) such that the needle (116) is blocked from movement in a direction parallel to the longitudinal axis thereof by a portion of the safety latch (122) distanced from the needle opening (129).