An autoinjector including a housing, in which can be mounted a syringe having a plunger, a barrel and needle at one end thereof through which medicament can be delivered to an injection site a syringe support means capable of causing said syringe to move therewith along an axial path with respect to said housing biasing means capable of biasing said syringe support means so that said needle is normally inside said housing, blocking means selectively moveable by a user from a first position in which rearward movement of the syringe along said axial path is substantially prevented, to a second position in which rearward movement of the syringe along said axial path relative to said housing is possible and said biasing means causes said needle to retract inside said housing.