Under-Eye RE2O Skin Booster — How Does It Fade Both Hollowness and Fine Lines at Once?
The under-eye area has some of the thinnest skin on your face. Filler adds volume; RE2O reinforces the dermal structure — here's how to choose the right approach for your case.

When dark, sunken under-eyes start to bother you, it's natural to look beyond eye creams and explore procedure options. Because the under-eye area has exceptionally thin skin, approaches like RE2O Skin booster — which work to reinforce the skin's texture from within — are often a more fitting choice than standard Filler.
> This article is an informational content piece summarizing procedures available at Beautystone Clinic in Hongdae.
In short, RE2O is an hADM*-based Skin booster that works by reinforcing the structure of the Dermis to fill in hollowed texture. Unlike Filler, which instantly adds volume, RE2O gradually stabilizes the dermal structure over time — which is why it's frequently used in thin areas like the under-eye zone to create a naturally softened appearance.
In this article, you'll learn:
· Why the under-eye area looks sunken — the structural reasons
· How RE2O Skin booster works
· Why RE2O and under-eye Filler produce different results
· A guide to help you decide whether RE2O is right for your under-eye concerns
Why the Under-Eye Area Looks Sunken: The Structural Reasons
The under-eye area is one of the thinnest-skinned regions on the face. The epidermis and Dermis here are roughly half the thickness of other areas, which makes the underlying blood vessels, muscles, and bone contours far more visible. The appearance of hollowness typically involves a combination of three distinct patterns.
- Vascular type: The color of blood vessels (blue or purple) shows through the thin skin
- Pigmentation type: Melanin deposits beneath the skin create a brown or grayish tone
- Structural type: Weakening of the supportive layer (Dermis) beneath the eye leads to a sunken appearance
In many cases, all three are present simultaneously. DermNet's resource on under-eye dark circles also breaks down the causes into several categories: increased pigmentation, vascular show-through due to thin skin, and shadows caused by fat loss and structural changes around the eye. The "hollowed" look itself stems from weakening of the dermal structure rather than pigmentation — which is precisely why the procedural approach differs.
How Does RE2O Skin Booster Work?
RE2O is an hADM-based Skin booster. It works by entering the Dermis and reinforcing its structure from within. Rather than immediately adding volume, it gradually stabilizes the dermal framework — which is why results emerge progressively over a period of one to three months following the procedure.
hADM* (human acellular dermal matrix): A matrix-form component derived from human dermis in which all cellular elements have been removed, leaving only structural proteins such as Collagen. Once placed in the Dermis, it acts as a supportive scaffold.
Because the epidermis and Dermis are both thin in the under-eye area, understanding which layer RE2O settles into — when viewed in cross-section — makes its mechanism of action considerably clearer.

A clinical study evaluating injectable human acellular dermal matrix as a skin booster reported that this ingredient acts as a scaffold for dermal remodeling, with improvements observed in skin density, Elasticity, and wrinkle depth. When the Dermis is reinforced, the overlying epidermis is naturally lifted — causing both hollowness and Fine Lines to soften simultaneously. It's less about filling a single point, and more about lifting the overall texture from beneath.
Why Under-Eye Filler and RE2O Produce Different Results
Both Filler and Skin booster are available as under-eye procedure options. The reason they deliver different outcomes comes down to their distinct mechanisms of action.
| Procedure | Mechanism | Immediate Change | When Results Stabilize | Naturalness |
|---|---|---|---|---|
| Filler (HA) | Immediately adds volume | Yes | 1–2 weeks post-procedure | Varies by area and technique |
| RE2O Skin Booster | Reinforces dermal structure | Some Swelling only | 1–3 months post-procedure | Natural, gradual softening |
| Rejuran line | Sends skin recovery signals | Some Swelling only | 2–3 weeks post-procedure | Texture correction and tone |
As noted above, Filler immediately fills in sunken areas to deliver fast, visible results. However, in thin-skinned areas like under the eye, placement that's too deep can lead to puffiness or a lumpy appearance — which is why practitioner experience is critical. RE2O takes longer, but by lifting the overall texture from below, it creates a more natural softening rather than a volumized look.
If your under-eye concern looks like "one specific point that's visibly sunken," Filler tends to be the better fit. If it looks more like "overall thin, crepey texture with Fine Lines throughout," RE2O is generally the more appropriate approach. That said, if your dark circles are primarily brown and pigmentation-driven, they're more likely to be influenced by UV exposure and hormones — similar to melasma — and RE2O alone may not be sufficient, requiring a different treatment approach altogether.
At Beautystone Clinic in Hongdae, We Stage Each Procedure Separately
At Beautystone Clinic in Hongdae, we don't rush through everything in a single session. Instead, we stage each procedure separately, reviewing your results along the way. For under-eye RE2O cases as well, we assess outcomes at 4–6 weeks after the first session before deciding whether to proceed with additional rounds.
Since dermal reinforcement accumulates progressively with each session, we generally recommend a step-by-step approach — proceeding one session at a time while monitoring your individual Recovery — rather than bundling multiple rounds upfront. The clinic is within walking distance of Hapjeong Station, making it easy to stop by briefly between sessions to check your progress and adjust your schedule accordingly. Even with the same RE2O procedure, tailoring the staging to your specific under-eye condition is what makes the difference in achieving a natural-looking result.
A Guide to Whether RE2O Is Right for Your Under-Eye Concerns
If most of the following apply to you, RE2O Skin booster is likely a fitting approach to consider.
- Your overall under-eye texture is thin and Fine Lines are present throughout
- The hollowness is diffuse — not a single localized indentation
- You've had Filler before and found the results looked lumpy or unnatural
- You prefer a gradual, natural softening and aren't concerned about immediate results
On the other hand, if any of the following apply, we'd typically guide you toward Filler or a different approach instead.
- There's one clearly defined sunken point (with strong vascular or bone show-through)
- You need visible results within a short timeframe (e.g., an event within two weeks)
- Pigmentation-type dark circles are your primary concern
The chart below gives a general sense of how under-eye texture tends to shift as RE2O sessions accumulate over time. Keep in mind this reflects average trends — individual Recovery rates vary considerably from person to person.

If you're unsure which category your under-eye concerns fall into, the safest approach is to have a Wood's lamp assessment during your consultation so we can evaluate and decide together.
Frequently Asked Questions
Q. Can I notice a difference after just one RE2O session?
A. Subtle textural changes typically begin to appear around 4–6 weeks after the first session. That said, RE2O is a procedure where results accumulate with each session — results generally stabilize at 1–3 months after completing multiple sessions. Rather than expecting a dramatic change from a single session, a step-by-step approach is recommended.
Q. How long does Swelling last after the procedure?
A. Mild Swelling and Erythema immediately following the procedure typically resolve within 1–3 days. Because the under-eye skin is so thin, Swelling may appear slightly more noticeable here than in other areas. It's advisable to avoid saunas and intense exercise for the first 24 hours after the procedure.
Q. Can I receive both Filler and RE2O at the same time?
A. Combining both procedures in the same session is not recommended. When the effects of both overlap, it becomes difficult to assess which procedure is driving the results, and there's a risk of cumulative Swelling or hypersensitivity reactions. The standard approach is to proceed with one procedure first, evaluate the outcome, and then decide on the next step.
Q. How long do the results last?
A. Results following a completed course of RE2O sessions tend to be maintained for approximately one to two years. The duration can vary depending on your individual Collagen Recovery rate and lifestyle factors such as sun exposure and sleep quality. Since Sunscreen use and daily skincare habits are key to sustaining results, it's best to discuss a combined procedure and Aftercare plan with your physician.








