What Is Better for Fine Lines Under the Eyes: Rejuran I or Juvelook?

Fine lines under the eyes can make your face look tired, even when you feel well-rested. If you are considering Korean aesthetic treatments, Rejuran I and Juvelook may both come up during a consultation. However, they have different formulations and should not be treated as interchangeable products.

Rejuran I may be worth discussing when the main concern is delicate under-eye skin quality and fine lines. Juvelook may be considered for selected cases involving under-eye texture, fine lines, or tear-trough changes. Neither treatment is guaranteed to remove wrinkles, and there is not enough strong comparative evidence to establish one as universally better.

The right choice depends on whether your lines are caused by dryness, facial expressions, skin aging, or hollowing beneath the eyes.

Why Do Fine Lines Develop Under the Eyes?

The skin around the eyes is naturally thin and moves frequently during blinking, smiling, and other facial expressions. As skin ages, changes in collagen, elasticity, hydration, and underlying support can make lines more visible.

Common causes include:

• Dehydration: The skin may look finely creased when it lacks moisture.
• Natural skin aging: Gradual changes in collagen and elasticity can make fine lines more noticeable.
• Repeated facial expressions: Smiling and squinting can contribute to expression lines.
• Sun exposure: Ultraviolet radiation contributes to premature skin aging.
• Under-eye hollowing: Loss of volume can create shadows and folds that resemble wrinkles.
• Puffiness or dark circles: These can make the under-eye area look more tired, but they are different concerns and may require different treatments.

Identifying the cause is essential. An injectable intended to improve skin quality may not correct prominent expression lines, deep hollows, or persistent under-eye bags.

1. Rejuran I for Under-Eye Fine Lines

Rejuran I is a polynucleotide-based injectable formulation used for delicate areas, including the under-eye region. Polynucleotides are intended to support skin-quality improvement rather than provide the same type of structural correction as a conventional volumizing filler.

Who may consider Rejuran I?

A dermatologist may discuss Rejuran I if you have:

• Fine lines in the under-eye skin.
• Early signs of reduced skin elasticity.
• A crepey or uneven skin texture.
• Mild skin-quality changes without substantial under-eye hollowing.

It may be particularly relevant when your goal is gradual improvement in the appearance of the skin rather than adding noticeable volume.

What results can you expect?

Research on polynucleotide injections for the under-eye area is encouraging but still developing. A prospective observational study published in 2026 followed 42 patients receiving polynucleotide injections for under-eye wrinkles and reported improvements in patient-reported appearance and satisfaction. The greatest improvements were observed around three months after two treatment sessions.

However, the study used a polynucleotide product rather than establishing that every Rejuran I protocol will produce the same results. Observational findings also cannot prove that a treatment will work equally well for everyone.

Rejuran I should therefore be viewed as a possible option for selected fine-line concerns, not a guaranteed wrinkle-removal treatment.

What are the limitations?

Rejuran I will not reliably correct deep tear-trough hollows, significant bags, or every type of expression line. Injection-related discomfort, redness, swelling, bruising, and temporary bumps may occur.

Because the skin is thin around the eyes, the injection technique and the clinician's experience are particularly important.

2. Juvelook for Under-Eye Fine Lines

Juvelook combines poly-D,L-lactic acid (PDLLA) with hyaluronic acid (HA). It is used in aesthetic medicine to target selected skin-quality concerns through hydration and a longer-term tissue response.

Who may consider Juvelook?

Depending on the formulation and technique, a dermatologist may discuss Juvelook when under-eye concerns include:

• Fine lines and uneven texture.
• Reduced skin smoothness.
• Selected tear-trough changes.
• A combination of skin-quality concerns and mild contour irregularities.

The intended result depends on the treatment plan. Juvelook is not simply a stronger version of Rejuran I, and it should not be selected based on the assumption that collagen stimulation always produces a better outcome.

What does the research say?

A 2025 study evaluated PDLLA treatment for lower-eyelid rejuvenation in Korean women and reported improvements in tear-trough appearance and patient satisfaction during follow-up.

A separate prospective study published in 2026 evaluated PDLLA combined with HA for the tear-trough area in 15 women. It reported improvements in under-eye skin quality, hydration, elasticity, and radiance after three treatments.

These findings are promising, but the studies were small. They do not establish that Juvelook is better than Rejuran I for fine lines, and results from a selected study population may not apply to every patient.

What are the limitations?

The under-eye area is especially sensitive to swelling and irregularities. PDLLA-based injectables can also be associated with nodules or other injection-related complications. A published case report has documented nodules after a PDLLA-based product was injected into the tear-trough region.

This does not mean complications are inevitable, but it highlights why product selection, appropriate placement, and medical expertise matter. Juvelook should only be considered for the under-eye area when the clinician determines that the specific formulation and technique are suitable.

3. Rejuran I vs Juvelook: Which Is Better for Your Concern?

The best option depends on the problem you want to improve.

If your main concern is fine, crepey skin

Rejuran I may be worth discussing if the goal is to improve skin quality and the appearance of delicate lines. Juvelook may also be considered in selected cases, but the potential benefits and risks of each formulation should be assessed individually.

If your skin looks dry and crumpled

Begin by checking your skincare routine and skin barrier. A gentle cleanser, suitable moisturizer, and daily sunscreen may help when dehydration contributes to the lines.

An injectable may be considered if additional concerns remain, but neither treatment should be viewed as a substitute for appropriate skincare.

If you have under-eye hollows

Hollowing creates shadows that can make the area look wrinkled even when the skin itself is relatively smooth. A skin booster may not adequately address this structural concern.

A dermatologist should assess whether the problem is mainly skin quality, volume loss, pigmentation, or a combination of factors before recommending an injectable.

If you have prominent bags or puffiness

Neither Rejuran I nor Juvelook should be assumed to correct persistent under-eye bags. Some injectable treatments can temporarily worsen swelling, and the under-eye region is particularly prone to fluid accumulation.

If puffiness is your main concern, ask for an assessment before proceeding with an injection.

If you want the most natural-looking result

A natural result depends on selecting the correct treatment for the underlying concern, using an appropriate technique, and maintaining realistic expectations. The goal should be a subtle improvement that suits your anatomy—not simply choosing the product with the strongest marketing claims.

4. Are These Treatments Safe Around the Eyes?

The under-eye region contains delicate skin, important blood vessels, and structures that require careful handling. Even a treatment intended for skin rejuvenation can produce unwanted effects.

Possible side effects include:

• Pain or tenderness during treatment.
• Redness and bruising.
• Swelling or temporary bumps.
• Persistent lumps or uneven texture.
• Infection or inflammatory reactions.
• Rare but serious vascular complications associated with injectable procedures.

The exact risks vary by product, technique, injection depth, and individual anatomy. The absence of complications in a small clinical study does not establish that a procedure is risk-free.

Before treatment, ask your provider which product will be used, whether it is suitable for your under-eye anatomy, what complications to watch for, and how you can obtain medical help if you experience a problem.

5. What Should You Consider Before Treatment in Seoul?

If you are traveling to South Korea for under-eye rejuvenation, plan for consultation and recovery rather than scheduling injections immediately before an important event.

Before agreeing to treatment, ask:

• What is causing my under-eye lines?
• Is my main concern fine skin wrinkles, hollowing, or puffiness?
• Why do you recommend this particular product?
• What improvement is realistic?
• How many sessions may be needed?
• What side effects and follow-up care should I expect?

Do not choose a treatment solely because it is popular in Korean clinics. A qualified medical professional should assess your anatomy, medical history, previous injectable treatments, and individual risk factors.

If you are visiting for only a short time, make sure you have clear aftercare instructions and know how to obtain medical assistance after returning home.

Conclusion: Rejuran I or Juvelook for Under-Eye Fine Lines?

Rejuran I may be worth discussing for delicate under-eye skin-quality concerns and fine lines. Juvelook may be considered for selected cases involving texture, skin quality, and tear-trough changes. Current evidence does not establish that either treatment is universally superior.

If your lines are mainly caused by dehydration, skincare may be a sensible first step. If they are caused by hollowing, puffiness, or repeated facial movement, a different treatment may be more appropriate.

The safest approach is to identify the cause of the lines, discuss realistic results and risks with a qualified dermatologist, and choose a treatment based on your anatomy rather than the product name alone.

Frequently Asked Questions

1. Is Rejuran I better than Juvelook for under-eye wrinkles?

Not necessarily. Rejuran I is a polynucleotide-based injectable, while Juvelook combines PDLLA and HA. There is insufficient strong comparative evidence to prove that one is consistently better for under-eye wrinkles.

2. Which treatment is better for thin under-eye skin?

Rejuran I may be worth discussing when skin quality and fine lines are the primary concerns. However, suitability depends on the condition of the skin and the clinician's assessment. Neither product guarantees an increase in skin thickness.

3. Can Juvelook remove under-eye wrinkles?

Juvelook may improve selected aspects of skin quality and tear-trough appearance, but it cannot guarantee wrinkle removal. Deep folds, prominent bags, and expression lines may require different approaches.

4. Does Rejuran I cause swelling under the eyes?

Temporary swelling, bruising, redness, and injection-site bumps can occur. The duration and severity vary between individuals, so allow recovery time before important events.

5. Can Rejuran I or Juvelook treat dark circles?

Dark circles can result from pigmentation, visible blood vessels, hollowing, or shadows. These injections may help selected skin-quality concerns but are not reliable treatments for every cause of dark circles.

6. How many treatments are needed for under-eye fine lines?

The number depends on the product, the treatment area, and the clinician's protocol. Some plans involve several sessions, and visible improvement may take time. Ask for a personalized schedule and avoid assuming that one session will deliver the final result.