Hyaluronidases are enzymes that degrade hyaluronic acid (HA), a fundamental constituent of the extracellular matrix that can be injected subcutaneously for aesthetic purposes. These enzymes are widely employed in aesthetic medicine, due to their role in preventing complications from the inappropriate injection of HA, eliminating HA nodules, or correcting unsightly HA overfilling. Hyaluronidases have been employed for several years as a spreading agent to promote the diffusion of several substances injected subcutaneously, to remove the cumulus-corona-oocyte complex formed during intracytoplasmic sperm injection, to prevent tissue damage after extravasation of several substances, for edema reduction, and for treatment of vitreous hemorrhage.
It is essential for the aesthetic practitioner to have a sound knowledge of the indications, modalities of application, and adverse effects of hyaluronidases. However, although the indication, usage, effects, and complications of these enzymes have been reported for several applications, an extensive review of this topic in aesthetic medicine is lacking.