An autoinjector includes a housing (10) to receive a syringe (14), and a drive mechanism including first and second springs (30, 32) operating in tandem via an intermediate member (34), on a plunger (42). The plunger is retained in a locked position by a trigger. Release of the trigger causes the first spring to advance the syringe to an arrest point whereafter the second spring extends within the syringe to expel a dose.