How does hyaluronidase work? How Hylase dissolves hyaluronic acid filler

Hyaluronidase is the enzyme that breaks down hyaluronic acid filler in a targeted way: safely, in a controlled manner and, in the right hands, without lasting traces. If you are looking for a correction after a filler treatment, if you are living with asymmetry, hardening or an unwanted result, or if you simply want to understand how the breakdown works medically, you will find a factual explanation here.

What is hyaluronidase?

Hyaluronidase is an enzyme that occurs in the body, where its natural role is to break down hyaluronic acid in the tissue. It has been used medically for decades, originally as an aid to help medicines spread through tissue.

In aesthetic medicine we use it deliberately to dissolve hyaluronic acid filler. The preparation used for this is called Hylase. Hylase is the trade name for injectable hyaluronidase. In everyday clinical use the term is used interchangeably with the enzyme itself; medically speaking, Hylase is the preparation and hyaluronidase the active substance.

Hyaluronidase is obtained from bovine (animal) sources or produced synthetically as a recombinant protein. Both variants are established in medicine. At The Retreat Berlin we use exclusively tested preparations approved for human medicine.

→ More on filler dissolution at The Retreat.

How does hyaluronidase break hyaluronic acid down?

Hyaluronic acid is a long chain molecule, a polysaccharide made up of repeating sugar units. It is these chains that give filler its consistency and bind water in the tissue.

Hyaluronidase acts as a hydrolytic enzyme: it splits the glycosidic bonds between the individual sugar units of the hyaluronic acid chain. The result is shorter fragments, which the body breaks down and excretes through its normal metabolic pathways. The filler does not dissolve all at once; the process runs over hours to a few days, depending on the amount of filler and the degree of cross-linking of the material.

Cross-linked hyaluronic acid, as found in most aesthetic fillers, is harder to break down than uncross-linked material. That is why the necessary amount of enzyme and the exact placement of the injection are decisive: too little does not work sufficiently, too much can affect surrounding tissue unnecessarily.

Typical cases in which a targeted filler dissolution becomes necessary:

• Filler migration: hyaluronic acid has shifted out of its original area, for example upwards over the lip border
• Hardening and nodules: the material has distributed unevenly or was injected too superficially
• Asymmetry: one side is filled more than the other
• Overfilling: too much volume was placed and the result looks unnatural
• Tear trough filler: a frequently over-treated area in which precise corrections matter particularly

Is natural hyaluronic acid broken down as well?

This is the question we are asked most often, and it is a fair one.

The answer: yes, hyaluronidase can also break down the body’s own hyaluronic acid. That effect is temporary, however. The body produces hyaluronic acid continuously. The body’s own hyaluronic acid returns to its normal level within a few weeks.

What that means clinically: after a Hylase treatment the treated area can look somewhat flatter or less full for a short time. Swelling in the first 24 to 48 hours is normal and part of the physiological reaction to the enzyme, not a sign of a problem.

The decisive factor is dose and placement: an amount of hyaluronidase that is too high, or spread too broadly, breaks down more of the body’s own hyaluronic acid than necessary. That is exactly why precise work matters, and why at The Retreat Berlin we dissolve exclusively under ultrasound guidance.

Allergic reactions are possible but rare. For patients with a known allergy to bee or wasp venom, which also contains hyaluronidase, an allergy test before the treatment is sensible.

How is hyaluronidase used at The Retreat?

At The Retreat Berlin we carry out filler dissolution exclusively under ultrasound control. That is not the standard. It is a deliberate decision for greater safety and precision.

The procedure:

1. 01
   Ultrasound assessment before the treatment: before a drop of hyaluronidase is injected, we look with the ultrasound device to see where the filler actually sits. Filler does not always lie where it was injected. Migration is more common than people assume.
2. 02
   Targeted injection: the hyaluronidase is injected directly into the filler depot, not beside it and not superficially above it. Ultrasound makes it possible to judge depth, layer and volume in real time.
3. 03
   Monitoring during the dissolution: in complex corrections, the progress of the breakdown can be followed with ultrasound within the same appointment.
4. 04
   Aftercare: cooling measures directly after the treatment, and a follow-up after two to four weeks to assess the result and, if needed, plan a second treatment.

A complete correction can often be achieved in one session. With more heavily cross-linked material, or material that has been in place for a long time, a second session can be sensible.