Rocco Salvatore Calabrò, Piera Bonavita
BACKGROUND: Hyaluronic acid (HA) fillers are widely used for lip augmentation and are generally associated with a favorable safety profile. While vascular complications are well recognized, non-vascular neurological adverse events, including trigeminal neuropathic pain, remain underreported, particularly following procedures in anatomically lower-risk areas such as the lips. OBJECTIVE: To report a rare case of persistent trigeminal neuralgia-like pain following HA lip augmentation and to highlight diagnostic and therapeutic considerations. METHODS: A 49-year-old woman developed persistent facial pain 10 days after HA lip augmentation. Clinical evaluation included dental assessment, imaging studies, and high-resolution ultrasound of the perioral region. Initial management with hyaluronidase, corticosteroids, and non-steroidal anti-inflammatory drugs was performed. Due to persistent symptoms, a neuropathic pain-oriented treatment with pregabalin and palmitoylethanolamide (PEA) was initiated. Pain severity was assessed using a visual analog scale (VAS), and follow-up was conducted over 3 months. RESULTS: The patient presented with severe bilateral facial pain and paresthesia (VAS 7), refractory to conventional anti-inflammatory treatment. Imaging excluded dental pathology and vascular complications, while ultrasound revealed localized post-procedural tissue changes. Following initiation of pregabalin and PEA, a significant and sustained reduction in pain was observed (VAS 2 at 1 month; VAS 1 at 3 months). CONCLUSION: Persistent trigeminal neuralgia-like pain represents a rare but clinically relevant complication of HA lip augmentation. This case supports a neuropathic and neuroinflammatory mechanism and underscores the importance of early recognition and targeted treatment. Awareness of this complication may improve clinical outcomes and guide management strategies in aesthetic practice.