What is hyaluronidase?
Hyaluronidase is the enzyme that causes hydrolysis (the breakdown) of hyaluronic acid. Hyaluronic acid is the main constituent of various temporary dermal fillers, the names of which cannot be published here due to TGA restrictions.
Hyaluronic acid dermal fillers are commonly used for the treatment of lines, folds and wrinkles, and for the enhancement or volumisation of cheeks, lips, chins, and noses. Left alone, they are normally metabolised by the body over the period of 3 to 24 months (the longevity of these hyaluronic acid fillers depends on the type used and the area treated).
What is hyaluronidase used for?
Hyaluronidase is used to dissolve hyaluronic acid fillers that have been placed incorrectly, excessively, or unevenly. It is injected into the vicinity of the filler that needs to be dissolved. The action of hyaluronidase is very quick, and starts to work immediately, with most of the effect taking place within 24 hours.
One of the common filler areas that is dissolved is under the eyes. The skin here is particularly thin, and over treatment with dermal fillers is easily visible.
The reversibility of hyaluronic acid fillers with hyaluronidase means that there are very few permanent adverse outcomes from use of the hyaluronic acid fillers. For example, if a lump forms due to excess hyaluronic acid filler in one area it can be easily dissolved after the treatment.
What are the possible side effects of hyaluronidase?
Allergy is an uncommon side effect of use, and is more common in those allergic to bee-stings! The injection hyaluronidase can also cause bruising.
The most difficult aspect of using hyaluronidase is judging the amount required to dissolve a certain amount of filler. It is quite easy to over or under-dissolve hyaluronic acid fillers. Therefore, a second or third visit may be required to add more filler if over dissolved, or to retreat with hyaluronidase if under-dissolved.