Safety Assessment of Microneedle Technology for Transdermal Drug Delivery: A Review

The promising development of the microneedle (MN) drug delivery system has prompted its clinical application as a substitute for traditional hypodermic injection needles. In addition to the satisfactory MN technology design for various application prospects, safety issues during MN use are increasingly an important consideration. This review aims to gather data from published literature regarding safety evaluations on MNs in relation to pain, skin irritation, in vivo degradation, as well as storage stability. By analyzing the existing testing methods and the safety performance of MNs, the description of MN safety is updated as painless, minimally invasive, and stable during storage. However, the development of MNs that can degrade in a human body should be addressed to accelerate clinical applications.