Rumour: “If filler is dissolved, your face’s own tissue dissolves too” — What does the science say?

Short answer: hyaluronidase is an enzyme that breaks down hyaluronic acid. While dissolving the gel in the filler, it may also affect the natural hyaluronic acid in the area for a while; however, your skin’s own hyaluronic acid is constantly being broken down and rebuilt anyway. It does not dissolve tissues such as muscle, fat or bone. Its known side effects are mostly temporary; allergy can occur rarely. The procedure only works with hyaluronic acid fillers and should be carried out by a physician.

Where does the rumour come from?

An important feature of hyaluronic acid filler is that it can be dissolved if needed. To do this, the physician injects an enzyme called hyaluronidase into the area. After dissolving, some people feel that the area looks emptier or more sunken than it did before the filler. This gives rise to the belief that the enzyme dissolves not only the filler but also the face’s own tissue.

The rumour does have a basis: our skin and connective tissue also naturally contain hyaluronic acid, and the enzyme does not distinguish between the hyaluronic acid in the filler and that in the body. The myth goes wrong when, starting from this fact, it concludes that the effect is permanent and destructive.

How does hyaluronidase work?

Hyaluronidase is a group of enzymes that also occurs naturally in our body. Its job is to split the long chains of hyaluronic acid into smaller pieces. It has been used in medicine for many years, for example to help some medicines spread more easily into tissue. In aesthetic medicine, it is used to dissolve hyaluronic acid filler.

The enzyme mainly targets hyaluronic acid. It does not dissolve structures such as muscle, fat, bone or collagen, the supporting fibres of the skin. It also becomes inactive in the tissue within a short time; so its effect remains limited to the area where it is injected and to a short period of time.

What happens to the body’s own hyaluronic acid?

Laboratory and small clinical studies have shown that injected hyaluronidase can also break down the natural hyaluronic acid in the tissue. So this part of the rumour is not entirely unfounded.

However, the hyaluronic acid in our body is not a substance that stays fixed. According to scientific sources, about a third of the hyaluronic acid in an adult’s body is broken down and rebuilt every day; in the skin, this cycle is completed within a short time, a matter of days. For this reason, the enzyme’s effect on natural hyaluronic acid is expected to be temporary.

We need to be honest here: studies measuring exactly how long it takes for natural hyaluronic acid to return to its previous level in healthy human faces after dissolving are limited. Current knowledge does not show any permanent tissue loss; however, more research is needed for precise timescales.

Why can the area look sunken after dissolving?

There are several explanations for this perception. First, the person has become used to the filled appearance over months or years; when the filler is removed, the area looks emptier compared with what they are used to. In addition, the face has continued to age while the filler was there, and the resulting appearance may differ from photos taken before the filler.

Swelling in the first days after dissolving, and then this swelling going down, also make the appearance changeable. Some physicians describe a short-term loss of volume after dissolving; the evidence on how often this happens and how long it lasts is limited. A period of waiting is usually needed to assess the final appearance of the area, and if new filler is being considered, its timing is planned with the physician.

What are the real risks?

Hyaluronidase is also a medicine and has side effects. The most common are temporary swelling, redness, tenderness and itching at the injection site. Allergic-type reactions to the enzyme have been reported; most of these are local and mild. Serious allergic reactions, such as widespread hives or swelling of the lips or tongue, are rare. Because the risk may be higher in people who are allergic to bee or wasp stings, be sure to tell your physician about this. Some physicians may do a small skin test before the procedure; however, this test cannot always predict allergic reactions that start later.

In an emergency such as vascular occlusion, however, time is very important, and the benefit the enzyme can provide usually outweighs the risk of possible side effects. This decision is made by the physician assessing the emergency. For filler-related emergency symptoms, see our article “After Fillers: When Is It an Emergency?”.

For other forms of allergy and what to do, you can read our article “Allergic Reactions in Aesthetic Treatments”.

Which fillers can be dissolved?

Hyaluronidase only dissolves hyaluronic acid fillers. Fillers that are permanent or made of substances other than hyaluronic acid cannot be dissolved with this enzyme. This is why it is important to know the type of filler you have had before. For types of filler and possible problems, see our articles “Hyaluronic Acid Filler” and “Filler Complications”.

Why should only a physician do it?

• First, whether the problem is really related to the filler, and the type of filler, must be determined by an examination.
• The amount of enzyme and the injection points are planned by the physician according to the type of problem and the area.
• A healthcare facility where immediate action can be taken if an allergic reaction develops is needed.
• Dissolving products sold online or home treatments may contain products of unknown origin and carry serious risks; do not use them.

Conclusion

There is no evidence that the face’s own tissue is permanently dissolved when filler is dissolved. The enzyme targets hyaluronic acid and may temporarily affect the natural hyaluronic acid in the area; the body, however, constantly renews this substance. The real risks are mostly temporary side effects and rare allergy. The decision to dissolve filler should be made together with your physician after an examination.