Filler not dissolved, I am afraid of doing hyaluronidase. Is filler toxic for nerves?

Hello! My name is Jessica, I am a physician assistant, and one of the providers at Aesthetic Skin - Winnetka & Chicago. This is a great question. It’s not uncommon for dermal fillers like Restylane (which is made of hyaluronic acid) to persist longer than expected, especially in areas with low mobility like the cheeks. While most HA fillers are marketed to dissolve within 6–18 months, studies and clinical observations—including findings from ultrasounds and MRIs—have shown that filler can sometimes remain for years. The fact that your MRI still shows presence in the same area after three years suggests that what’s seen is likely residual filler, although in rare cases, tissue changes or granulomas could also appear similar on imaging. The neurological symptoms you experienced after injection, including what now may be diagnosed as neuropathy, are concerning and suggest the filler may have caused prolonged pressure or inflammation near facial nerves. While hyaluronic acid itself is biocompatible and not inherently toxic, improper placement or vascular compromise can trigger a cascade that may affect nerve health. Given your history, and if the persistent filler is suspected to be contributing to your symptoms, dissolving it with hyaluronidase is a reasonable and often effective option. While it’s normal to feel anxious about the enzyme—especially if your experience with the filler was traumatic—hyaluronidase is widely used in medical practice and generally safe when performed by a skilled professional. A cautious approach could involve a test patch or a small dose to monitor your body’s response before proceeding with full dissolution. Ultimately, removing the remaining filler may help relieve pressure or irritation on affected nerves, and even if it doesn’t reverse all symptoms, it may prevent further aggravation. I hope this helps and best of luck!