Sustainable release artifact in PLGA microspheres for prolonged local aesthetics in postoperative pain management

The challenge of effectively managing long-term pain after surgery remains a significant issue in clinical settings. Although local anesthetics are preferred for their effective pain relief and few side effects, their short-lasting effect does not fully meet the pain relief needs after surgery. Articaine, widely used for postoperative pain relief as a local anesthetic, is pharmacologically limited by its short half-life, which reduces the duration of its pain-relieving effects. To overcome this issue, this study presents a new approach using poly (lactic-co-glycolic acid) (PLGA) microspheres for controlled articaine release, aiming to extend its analgesic effect while reducing potential toxicity. The PLGA microspheres were shown to extend the release of articaine for at least 72 h in lab tests, displaying excellent biocompatibility and low toxicity. When used in a rodent model for postoperative pain, the microspheres provided significantly prolonged pain relief, effectively reducing pain for up to 3 days post-surgery, without causing inflammation or tissue damage for over 72 h after being administered. The extended release and high safety profile of these PLGA microspheres highlight their promise as a new method for delivering local anesthetics, opening up new possibilities for pain management in the future.