Efficacy and Safety of Platelet-Rich Plasma and Hyaluronic Acid Combination Treatment for Neck Rejuvenation in Thailand: A Prospective Study

INTRODUCTION: Combined platelet-rich plasma and hyaluronic acid (PRP-HA) offers a promising nonsurgical technique for tissue regeneration through synergistic efficacy and longevity effects. This study aims to investigate PRP-HA's efficacy and safety for neck rejuvenation. METHODS: This 32-week prospective trial enrolled 30 Thai participants with mild-to-moderate neck aging. Treatment consisted of three monthly intradermal PRP-HA injections to the anterior neck surface, with follow-ups at 2 weeks, and 1, 2, 3, and 6 months posttreatment completion. Assessment included skin firmness, elasticity, biometric parameters, pain scores, and adverse effects. RESULTS: Of 29 completing participants, neck skin firmness improved 54% from baseline at 3-month posttreatment completion, increasing to 65% at 6 months (p < 0.0001). While gross elasticity initially improved at 1 month posttreatment (p = 0.0217); it subsequently declined. The 6-month follow-up showed substantial reductions in melanin and erythema (p < 0.01). Sustained improvements were observed in hydration through study completion (p < 0.01). Sebum levels decreased significantly after the first two treatments and at 3 months posttreatment (p < 0.05). No significant changes appeared in skin texture, wrinkles, and brightness. Most participants reported 51-75% improvement after the third treatment, maintaining through 6 months. No severe adverse effects were reported. CONCLUSIONS: PRP-HA demonstrates safe and effective improvements in neck skin firmness, hydration, and pigment and sebum regulation, with benefits lasting 6 months after three treatment sessions. However, variable effects on elasticity and modest results on wrinkles, texture, and brightness warrant further controlled trials to further elucidate and confirm its rejuvenative properties on the neck. TRIAL REGISTRATION: This trial is registered under the Thai Clinical Trials Registry (TCTR20230212003).