A single use syringe in which the single use aspects are accomplished by a lumen spike which is forced into the lumen bore to seal the passageway from the syringe body to the hypodermic needle. Fail-safe characteristics to prevent bypassing the single use provisions are provided by having a frangible area of the endwall holding the lumen break out at a force less than that required to force the lumen spike out of the lumen bore. This aspect can also be used to improve other approaches to single use syringes. The lumen spike can be formed as part of the piston/plunger and the piston/plunger can be a unitary device useful in all syringes.