A detailed review of the recent development of needle-free drug delivery devices.

This study aims to highlight the noteworthy impression of the needle-free drug delivery devices to endorse drug delivery technology innovation. By briefing existing information, this assessment can guide the development of a new device. A thorough literature survey has been done to analyse the design, technology mechanism, CFD studies, clinical results, and patents filed in the field of such devices. Challenges and future scope of improvement in the existing devices were reported. A number of drug delivery devices were investigated and have been reported in this study. Among all the reported devices, the shock wave-operated device has the ability to reduce the current limitations in needle-free drug delivery device, offering a usable solution for treating diseases. Most devices were developed for liquid vaccination, and trials were done both on animals and humans. Clinical trial evidence shows that these systems were acceptable to clinicians as well as patients. Several parameters can be modified to attain the required depth of penetration under the skin.