Chitosan, a Natural Polymer, is an Excellent Sustained-Release Carrier for Amide Local Anesthetics.

Local anesthetics, particularly amide types, play a crucial role in perioperative anesthesia to alleviate pain and manage chronic, long-term pain, with their brief effect period remaining a universal challenge that needs resolution. There is a high anticipation for creating materials that maintain prolonged effectiveness of local anesthetics through a straightforward administration technique. Chitosan is the most typical natural amino polymer, which is highly reactive and easy to modify. It has been widely and deeply used in the field of medicine. At present, it is mainly used in tissue regeneration and repair, hemostasis and wound healing, antibacterial and anti-infection, disease diagnosis and treatment detection, and drug delivery. In the field of anesthesia, chitosan is regarded as a potential perfect carrier for the sustained release of amide local anesthetics. This document aims to analyze the current application of chitosan as a prolonged-release substance in amide-type local anesthetics, encapsulate the associated research advancements, and subsequently investigate the practicality and prospects of its medical uses.