Abstract
The use of microneedles (MNs) has been established as an effective transdermal drug delivery strategy that has been extensively deployed for treating various diseases, including skin diseases. MNs can surpass the constraints of conventional drug delivery methods by their superior safety and efficacy through precise targeting, while simultaneously enabling painless delivery. Currently, MNs are increasingly used as carriers for drug delivery, with the loading of insoluble drugs to improve their treatment efficiency or combining with bioactive substances for the construction of an efficient drug delivery system to maximize the effects of bioactive substances. The methods used for preparation MNs are diverse, enabling them to meet the requirements of most applications. The emergence of MNs has addressed the shortcomings associated with insoluble drugs, expanded the applications of bioactive substances, and improved their use in clinical practice. This review summarizes current information on the application of MNs in a variety of skin diseases, such as psoriasis, vitiligo, alopecia, hypertrophic scarring, atopic dermatitis, melanoma, acne, and skin infections. The current clinical applications and future opportunities for MNs in the treatment of skin diseases are also discussed. Despite substantial progress in the clinical application of MNs as delivery vectors, issues such as low drug loading and poor mechanical strength during MNs preparation remain the main challenges. Therefore, clinical implementation of MNs-based therapies remains limited, highlighting key opportunities for future research.