title: Delayed hypersensitivity reaction to Restylane ® SubQ.
abstract: OBJECTIVE
  To report on 4 patients who developed delayed hypersensitivity reactions to Restylane(®) SubQ and their management. To our knowledge, no cases of delayed hypersensitivity to Restylane(®) SubQ have been previously reported.
  
  
  METHODS
  A retrospective case series of 4 patients who were treated with preperiosteal Restylane(®) SubQ to their cheeks, for facial volume augmentation. All 4 patients were subsequently referred with delayed hypersensitivity reactions over a 4-month period.
  
  
  RESULTS
  The hypersensitivity reactions occurred from 1 week to 4 months' post-cheek augmentation using Restylane(®) SubQ. All patients had previously (and some since) been treated with other non-animal stabilized hyaluronic acid (NASHA) products without adverse effect. Hyaluronidase led to fast and effective resolution in all cases, although 2 of the patients required repeat treatment.
  
  
  CONCLUSIONS
  Hyaluronidase was effective at treating the inflammatory reaction and breaking up the retained Restylane(®) SubQ in all patients. Although Restylane(®) SubQ should be avoided in these patients, in our experience this does not preclude them from using other similar NASHA products.
authors.affiliation: Corneoplastic Unit, Queen Victoria Hospital, East Grinstead, West Sussex, UK. mrphiliporeilly@gmail.com
authors.forename: Philip
authors.initials: P
authors.lastname: O'Reilly
authors.forename: Raman
authors.initials: R
authors.lastname: Malhotra
mesh_terms: D000328:Adult; D005148:Facial Dermatoses / Q000139:chemically induced*; D005260:Female; D006801:Humans; D006820:Hyaluronic Acid / Q000009:adverse effects / Q000031:analogs & derivatives*; D006968:Hypersensitivity, Delayed / Q000209:etiology*; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D006820:Hyaluronic Acid; C445361:Restylane