Background: Hyaluronic acid (HA) (Restylane and Hylaform) is becoming more widely used for cosmetic procedures such as lip augmentation and treatment of facial skin lines, as other products, mainly bovine collagen, have proved allergenic in many patients.
Objective: To report a case of a 48-year-old woman who developed discrete nodules in the lips after HA injection for lip augmentation. The histologic analysis revealed the presence of a granulomatous reaction surrounding a blue amorphous material with the tinctorial features of HA.
Conclusion: To our knowledge, this is the third case of granulomatous body reaction against this substance, which was allegedly inert in humans. Although rare, this reaction can have important aesthetic implications, and the patients should be informed about their risks.