Injections that dissolve filler (hyaluronidase)

What is hyaluronidase?

Hyaluronidase is an enzyme that breaks down hyaluronic acid, a major component of the matrix outside the cells ^[1]. It was first discovered in bacteria and is widely found in nature, including in insects, snakes, fish, and mammals ^[1]. Six types of hyaluronidase have been identified in humans ^[1].

In clinical practice, animal-derived products obtained from the testes of cattle or sheep, as well as synthetic products, are used ^[1]. It is used to help the body absorb other drugs, to treat drugs that have leaked out of a blood vessel, and to manage complications of hyaluronic acid filler treatment ^[1].

How hyaluronic acid fillers and the enzyme are related

Hyaluronic acid is the most commonly used filler ingredient ^[2]. Because it is a substance naturally found in the skin, the risk of an immune or allergic reaction when it is injected is described as very low ^[2]. Hyaluronic acid is found throughout mammalian tissues and can form a gel even at a concentration of 1% ^[5].

Because hyaluronic acid fillers are quickly broken down when hyaluronidase is injected, they are regarded as a low-risk, reversible injectable material ^[2]. A 2024 literature review considered that this ability to reverse complications contributed greatly to the widespread use of hyaluronic acid fillers ^[3]. On the other hand, because this enzyme breaks down hyaluronic acid, it cannot be assumed to work the same way on fillers made of other ingredients.

When is it used?

A 2024 literature review summarized non-emergency complications and emergency complications separately ^[3]. Non-emergency complications include the Tyndall effect, in which filler injected too shallowly shows through as a bluish tint, nodules without inflammation, and allergic or hypersensitivity reactions, and the review recommended treating these with low to moderate doses ^[3].

For inflammatory nodules, it stated that hyaluronidase can be considered after or together with oral antibiotics, and that it can be tried for granulomas (lumps formed by an immune reaction) that do not respond to steroid injections into the lesion ^[3]. It summarized that emergency complications such as vascular occlusion and blindness require immediate treatment with high doses ^[3].

• Tyndall effect
• Nodules without inflammation
• Allergic or hypersensitivity reactions
• Inflammatory nodules (considered together with antibiotics)
• Granulomas that do not respond to steroids
• Emergencies such as vascular occlusion and blindness

Its role and limits in emergencies

Blood vessel damage caused by filler is a serious adverse reaction that can lead to tissue necrosis (death of tissue) and, in rare cases, loss of vision ^[6]. In these situations, hyaluronidase is an important treatment, but it is not a cure-all. A literature review of nonsurgical rhinoplasty stated that hyaluronidase may be partially effective when signs and symptoms are detected early, while emphasizing that the best approach is still prevention ^[4].

When blindness occurs, whether the enzyme should be injected behind the eyeball or above the brow is still debated ^[3]. It has been reported that using ultrasound guidance at the same time may improve the effectiveness of this treatment ^[3].

Safety and questions that remain unresolved

According to a 2024 literature review, the hyaluronidase products currently in use are regarded as showing good results and having an acceptable level of safety ^[3]. However, data from controlled studies are limited, and opinions still differ on treatment methods, including dose recommendations ^[3]. Other issues covered in this review included the timing and dose of treatment, skin testing before treatment, the different properties of each product, and how they interact with filler gels ^[3].

The researchers concluded that medical staff who perform cosmetic procedures should be familiar with how to use hyaluronidase and with guidelines on effective doses ^[3]. How well a filler is broken down by the enzyme and what treatment is needed can vary depending on the situation and the person.

What to check during your consultation

Hyaluronidase is a drug used to adjust filler results or treat complications, so whether to use it should be decided after your condition has been checked through an examination. In particular, if a vascular complication is suspected, time matters, so you should let the clinic that treated you know as soon as symptoms appear.

• The ingredients, timing, and areas of filler you have had before
• Any symptoms that are bothering you now and when they started
• Your history of allergies
• The changes to expect after the enzyme injection and whether further treatment may be needed