Delayed Inflammation Occurred Only to VYC-25L After Coinjection of VYC-20L and VYC-25L in an Asian Patient

Delayed inflammatory reactions (DIRs) following hyaluronic acid filler injections are uncommon but pose significant clinical challenges. We report a 23‑year‑old Asian woman who developed a selective DIR confined to her chin after receiving a 4-mL VYC‑25L injection. Mild redness on the chin emerged 1 month postinjection, resolving after botulinum toxin treatment for mentalis hyperactivity. Seventy days postinjection, following dental procedures, the patient developed acute chin edema, pain, and redness. Magnetic resonance imaging demonstrated localized inflammation without abscess formation. Emergency hyaluronidase administration resulted in rapid symptom resolution. This case highlighted selective DIR to VYC-25L in an Asian patient, potentially associated with a large-volume, single-plane injection into an area of elevated tissue tension. Preventative strategies, including pretreatment muscle relaxation, staged injections, volume limitation, and dual-plane placement, are proposed in this case report.