Needle‐Free Jet Injectors for Dermal and Transdermal Delivery of Actives

Needle‐free jet injectors are medical devices used for the delivery of liquid medications across the skin as a high‐speed stream of fluid, without the use of a needle. The absence of a needle abolishes the risk of needle‐stick injuries, frequent among healthcare providers, and increases the compliance to injections in needle‐phobic patients. Through the modulation of several parameters of the jet injectors, the liquid medication can be delivered to different sites within or below the skin, thus allowing the use of such devices for both local and systemic therapies in a multitude of disorders. In the present chapter, after a brief historical overview, the functioning principles and the rationale behind the use of needle‐free jet injectors are presented. Moreover, preclinical and clinical studies where jet injectors have been employed for the systemic or local delivery of therapeutics are reviewed. Finally, in the last section, the potential of such devices for the administration of nano‐ and micro‐particulate drug delivery systems is discussed.