An Evaluation of the Analgesic Effect of Injection Pain in the Correction of Nasolabial Folds with Lidocaine-Containing Injections Using Modified Sodium Hyaluronate Gel (HA-L)

Objectives: To evaluate the analgesic effect and clinical value of hyaluronic acid gel (HA-L) containing 3 mg/mL lidocaine (0.3%) hydrochloride in the correction of nasolabial fold wrinkles. Methods: Forty female patients (44±11) years old with bilateral moderate~ severe nasolabial fold wrinkles were included in a double-blind, self-controlled trial, and randomized into groups of 20 each, using a stratified injection technique (1.5 mL≤per side), with HA-L (20 mg/mL sodium hyaluronate + 3 mg/mL lidocaine (0.3%)) injected on the left in one group, and regular HA gel injected on the right; in the other group, right injection of HA-L (20 mg/mL sodium hyaluronate + 3 mg/mL lidocaine (0.3%)) and regular HA gel on the left side. Results: The immediate pain NRS score was 48.8% lower in the test group compared with the control group (2.02±1.86 vs 3.95±2.11, P<0.001), and the analgesic effect lasted for 60 minutes. The improvement rate of WSRS at 14 d postoperatively was 100% in both groups (both scores improved≥ 1 points), and there was no difference in GAIS satisfaction rate (95.0% vs 97.5%, P>0.05). Meanwhile, the HA-L group had a 17.6% reduction in pain-related adverse reactions (35.0% vs 42.5%) and no increased risk of swelling and hardening (P>0.05). Conclusions: Hyaluronic acid gel containing 3 mg/mL lidocaine (0.3%) did not affect the structural support and dynamic aesthetic effect of hyaluronic acid through precise local anesthetic dosing (3 mg/mL), significantly reduced injection pain, and provided a novel solution for triple optimization of pain management-cosmetic effect-safety for highly sensitive areas such as nasolabial folds, with significant clinical translational value.