Answer: Star Trek's Hypospray
In the Star Trek universe, Hypospray is a needle-less medical device designed to deliver fluid medications other substances into the patient without the use of a conventional needle-based injection. At first glance, it seems natural to have such a device on Star Trek. Such devices have long been considered a future invention and their appearance is not limited to the Star Trek universe.
Nevertheless, the inclusion of the Hypospray was not driven by the desire of the Star Trek authors to be cutting edge in all technological issues. In early scripts, physicians and show attendants used regular 1
As a result, the authors created the hypospray, a tool that delivered medical injections without a visible needle, as the tool applied a burst of targeted pressure to push the drug through the skin. Although never officially confirmed, it has long been rumored that the prop used in the original series was a misused and slightly modified fuel injector for automobiles. If so, that would be ironic, since one of the first cases in which a person was injected with something about the mechanism on which the Hypospray works was in 1937, when a worker was injected with diesel fuel from the engine injector worked on.