Hyaluronidase and Hyaluronic Acid fillers


  • Vascular occlusion may follow injection of Dermal Fillers containing Hyaluronic Acid
  • Hyaluronidase (Hyalase®) is an effective treatment

Hyaluronic acid (HA)- based dermal fillers are the most commonly used fillers in the aesthetics market. HA is responsible for maintaining hydration in the dermis.

Hyaluronidases are enzymes (endoglycosidases) that can depolymerise HA.

Hyaluronidase is licensed in the United Kingdom (I'm not sure about Ireland) for enhancing permeation of subcutaneous or intramuscular injections, local anaesthetics, and subcutaneous infusions, and to promote resorption of excess fluids and blood. or external compression.

Hyaluronidase has immediate effect and a half-life of two minutes with duration of action of 24 to 48 hours. Though it has a short half life, its effectiveness lasts longer.

Indications for Hyaluronidase

Vascular occlusion

  • Necrosis after dermal filler treatment is rare (≡ 0.001%)
  • Vascular compromise due to HA filler injection should be treated immediately
  • Skin with arterial compromise will have a slow capillary refill time and dusky or blue-grey-black appearance
  • Venous insufficiency will have a fast capillary time and bluish discoloration
  • Signs of impending necrosis also include pain and coolness of the skin
  • Hyaluronidase should be administered as soon as this complication occurs (within 4 hours)


  • Blindness due to periocular embolism of HA is instant and associated with excruciating ocular pain
  • The retinal circulation needs to be restored within 60 to 90 minutes
  • Transfer immediately to the nearest hospital eye department
  • Retrobulbar injection of hyaluronidase (150–200 units in 2–4mL of diluent) into the inferolateral orbit should be considered by practitioners who have appropriate experience and competence while waiting for an ambulance

Tyndall effect

  • Bluish hue of the skin (usually subocular) after HA injection
  • Treat with hyaluronidase

Allergic reaction to the HA dermal filler

  • If antihistamines or systemic corticosteroids fail,
  • Removal of the filler with hyaluronidase is appropriate


  • Hyaluronidase should be reconstituted with saline (less painful than with water)

Content by Dr Íomhar O' Sullivan. Last review Dr ÍOS 21/11/21.