Route · Injection

Hyaluronidase: the only entry on this site that is not trying to make anything look better

The antidote used when filler blocks a blood vessel. In a review pooling 21 studies and 231 patients, resolution was 78.4% for skin necrosis and 45.2% for visual impairment, and starting within six hours significantly improved outcomes. But two meta-analyses point opposite ways on dose.

Last checked Sep 21, 2026

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What it is: An enzyme that breaks down hyaluronic acid. Injected, it dissolves hyaluronic acid filler that is already in place.
What it is used for: It is also used when the shape of a filler is unwanted, but what this page is about is filler blocking a blood vessel.
How it is said to work: It cuts the hyaluronic acid chains that give filler its structure. When filler in and around a blocked vessel dissolves, blood can flow again.

There are no numbers and no citations in this box. What has been established, and how far, is below.

At a glance

Session length: 5–20 min
Pain: Moderate
Downtime: 0–2 days
Sessions: 1–3 sessionsUsed for a complication, it is sometimes repeated according to response. No standard protocol is settled.
How long it lasts: 0 monthsNot a procedure whose effect is maintained. Once filler is dissolved that is that, and what dissolved does not come back.
Relative cost: Lower
How well established: Moderate evidence

“Reported in a trial” means a number a study on this page actually reported. “Typical range” is not a measured value but roughly how it is usually done, and it varies by clinic and by person.

Cost is not an amount but a band: where this procedure falls when the ones on this site are lined up per session, or per area treated. Real prices differ several-fold by clinic and by how much is treated, so they are not given here. Surgery is measured on a different scale and cannot be compared with this band.

This is not how large the effect is but how well confirmed it is. It shows the highest grade among the findings on this page.

Korean classification Being checkedThe regulatory class has not yet been confirmed against a primary document. It will be filled in once it is.

This page has a different purpose from the other procedure pages here. What is on it is not a procedure meant to make anything look better.

Hyaluronidase is an enzyme that breaks down hyaluronic acid. Injected, it dissolves hyaluronic acid filler that is already in place.

There is one reason this page exists.

Hyaluronic acid filler rarely enters a blood vessel or compresses one shut. When that happens the skin that vessel was feeding can die, and if a vessel supplying the eye is blocked, sight can be lost. This drug is the only thing available then, and time decides the outcome.

What someone considering filler needs to know, we think, is not 'this can happen' but 'what exists when it does, and how fast it has to be'. So we gave it its own entry.

This page is not linked to any concern. Linking to it from a concern page would make it read as an option for making something better.

And none of the material here is from randomised trials. These are systematic reviews pooling case series and cohorts. Randomising in an emergency like this is difficult both ethically and practically. We accept that circumstance and still write down what the material is.

This site does not deal in prices, clinics or reviews. And this page is not emergency guidance — that belongs to clinicians.

What is established

Moderate evidence

Resolution differs sharply by site — and there is a figure of six hours

A 2026 systematic review and meta-analysis. MEDLINE, PubMed, Cochrane and Web of Science were searched from 2000 to February 2025 for randomised trials, cohort studies and case series using hyaluronidase for hyaluronic acid filler complications.

21 studies, 231 patients were included. Mean age 30.1; 90.9% were women.

The complications:

skin necrosis — 60.6%
visual impairment — 52.8%

The resolution rates are the most important numbers on this page.

skin necrosis — 78.4%
visual impairment — 45.2%

Put those two side by side. About eight in ten for skin; fewer than half for the eye.

And the authors found one more thing. Early intervention, within six hours, significantly improved outcomes.

How to read these numbers.

First, this is not randomised material. The journal assigns this paper level of evidence IV. What was pooled is mostly case series, and case series lean toward the cases that went well being reported. Real-world resolution may be lower than the figures above.

Second, what counts as 'resolution' may differ between studies. The abstract does not give the definition.

Third, the direction these numbers point is still clear. Resolution for visual impairment is a bit over half that for skin necrosis, and sooner is better.

So it sits at 'moderate evidence'. There is a fair amount of human material, the design is observational, and we note alongside that more than this is hard to expect in such a situation.

One thing to take from this entry: after a filler, severe pain, skin turning white or purple, or anything wrong with vision means contacting someone immediately — not in a few hours.

Open-label trial in people (21) · 231 participants · Compared with no control group (before-and-after only) · Funding not declared · Endpoint clinical events (cancers, lesion counts) PMID 41249530
Open-label trial in people (15) · 223 participants · Compared with no control group (before-and-after only) · Funding not declared · Endpoint clinical events (cancers, lesion counts) PMID 39214904

Not established

On dose, two meta-analyses point opposite ways

A 2024 systematic review and meta-analysis. Four international databases were searched from inception to December 2023 for studies reporting two or more patients given hyaluronidase for skin necrosis after hyaluronic acid filler. 15 studies, 223 patients.

The primary outcome was the pooled proportion of complete scar resolution.

Result: 77.8% (95% CI 65.5–86.6%). Certainty of evidence by GRADE: low.

Split by dose:

high dose (over 500 IU) — resolution 69.6% (95% CI 41.2–88.3%)
low dose (500 IU or less) — resolution 88.1% (95% CI 86.0–96.2%)
not statistically significant (p = 0.18)

Adjunct therapies had no statistically significant effect either.

Here is the most important disagreement on this page.

The 2026 review in the entry just above states that higher doses correlated with better resolution in skin necrosis. Yet in this 2024 review the low-dose figure was the higher one — not significantly so, but higher.

Two meta-analyses point opposite ways on the same question.

We will not say which is right. But we can write down why this happens: what they pool is case series. And in case series, worse cases get larger doses. Then 'high dose' and 'poor outcome' appear together, and whether that is the dose or the severity cannot be separated in observational material.

The 2024 authors ask for the same thing in their conclusion — future studies should give more granular detail on their protocols so that evidence-based guidelines can be formed.

So this entry is 'not established'. Neither 'more is better' nor 'less is better' is supported by this material.

Open-label trial in people (15) · 223 participants · Compared with another active ingredient · Funding not declared · Endpoint clinical events (cancers, lesion counts) PMID 39214904

Early research

The figure was higher when it was injected under ultrasound — but that is 4 studies and 55 patients

A 2025 systematic review and meta-analysis. Four international databases were searched from inception to September 2024 for sources with two or more patients receiving ultrasound-guided hyaluronidase for impending filler-induced facial skin necrosis.

4 studies, 55 patients were included.

Result: the pooled proportion of complete scar resolution after ultrasound-guided hyaluronidase is probably 94.6% (95% CI 80.6–98.7%). GRADE certainty: moderate.

The authors write that usual practice involves flooding 1500 IU into the suspect area. Image-guided administration has been reported to give better outcomes at lower doses, but no review had been done — hence this paper.

There was no statistical difference (p = 0.36) between injecting intra-arterially and injecting into the hyaluronic acid deposits.

How to read that 94.6%.

First, 4 studies and 55 patients. Compare that with the 231 and 223 above.

Second, and this matters most — two of the four used image guidance after conventional flooding with 1500 IU had failed.

Which way that pushes the figure is not simple. If only failures were gathered, those are harder patients, and 94.6% would be impressive. Conversely, who gets chosen for ultrasound can itself select the outcome. That problem never leaves observational material.

Third, this is 'impending' necrosis, which is not the same situation as necrosis already established.

So it sits at 'early evidence'. The direction is plausible and the size is small.

Open-label trial in people (4) · 55 participants · Compared with no control group (before-and-after only) · Funding not declared · Endpoint clinical events (cancers, lesion counts) PMID 39881073

Known risks

Allergic reactions occur. Hyaluronidase is generally animal-derived or a recombinant protein, and hypersensitivity including anaphylaxis has been reported. Anywhere using it should be prepared for that.
Your own hyaluronic acid nearby dissolves too. The area around the injection can temporarily lose volume.
Swelling, redness and bruising occur at the injection site.
You may not get the original shape back after dissolving. Worth knowing when using it to remove filler.
It does not reverse everything. In the material above, resolution for visual impairment was 45.2%.
It is a drug used only in clinical settings.

What is not established

There are no randomised controlled trials. All the material above is systematic reviews of case series and cohorts. Randomising in an emergency like this is hard ethically and practically.
Two meta-analyses point opposite ways on dose.
What counts as 'resolution' may differ between studies, and the abstracts do not define it.
Case series lean toward the cases that went well being reported. Real-world resolution may be lower than the figures above.
Which preparation, at what dilution, injected where is not yet standardised. The 2026 review concludes by calling for standardised protocols.
We have not yet opened the primary Korean regulatory classification, so it stays 'being verified'.

Whether to have it done is a decision to make with a doctor.

What this article relies on

PubMed — 미국 국립의학도서관 문헌 데이터베이스National Library of Medicine · Checked on 2026-09-16