Unlocking the potential of transdermal drug delivery

Transdermal drug delivery (TDD) has gained clinical approval over several decades, with extensive research dedicated to novel drug and device development. Despite notable research progress, the market adoption of TDD devices has not met anticipated levels, with oral administration and injection remaining predominant delivery methods. To maximize the potential of TDD, we identify bottlenecks hindering its widespread clinical application and propose promising research avenues. We begin by analyzing stringent demands necessary to truly benefit patients, addressing significant challenges in biomechanics, nanomedicine, and flexible electronics. Subsequently, we delve into skin anatomy, enhancement strategies, nano-carriers, and their underlining mechanisms, highlighting the importance and framework of quantitative modeling. Based on these discussions, we highlight the core strength of TDD, such as automatic precise administration based on feedback and high delivery efficiencies, especially applicable to localized conditions (e.g., central nervous system diseases, tumors). Finally, we envision the future of intelligent TDD device and its operation scenario, aiming to steer research efforts toward faster translation of laboratory innovations into widely used products for sufferers.