Rejuran Machine vs Hand-Injection: Which Method Is Right for You?

Eugene Lee • November 2, 2025

Introduction

When considering Rejuran skin-booster treatments, one of the key decisions is not just which product, but how it’s delivered. On one hand you have hand injections performed by a skilled dermatologist; on the other, machine-assisted (injector gun / meso-gun / multi-needle machine) delivery. Each method has its own advantages and trade-offs. Understanding them helps you choose what’s best for your skin and expectations.

What Is Rejuran & Why Delivery Method Matters

Rejuran uses polynucleotides (PN) or PDRN extracted from salmon DNA to regenerate and repair the skin — improving texture, firmness, pore size, and overall skin health. Because the injections are about delivering that active material evenly and at the correct depth into the dermis, the method of delivery can influence:

  • precision of placement
  • amount of product loss or leakage
  • downtime / comfort
  • uniformity of results

Hand Injection (Free-hand by Doctor)

✅ Advantages

  • High precision: The doctor can individually control depth, dosage per point, spacing between injections → useful especially around delicate areas (under-eyes, nasolabial folds).
  • Minimal product loss: Because the doctor injects point-by-point, less risk of leakage or diffusion into undesired layers.
  • Customizable: Skin thickness, texture, area morphology all can be taken into account by the provider.

⚠️ Trade-offs

  • Procedure time: Takes longer because each point is administered manually.
  • More discomfort / downtime: May have more visible “embossing” (small bumps) or swelling after treatment.
  • Highly dependent on the injector’s skill: A poorly performed hand injection can lead to uneven result or complications.

Machine-Assisted Injection

✅ Advantages

  • Faster: The device can deliver multiple micro-needles or automated injections quickly across wider areas.
  • More comfortable/weaker embossing: Because the machine may deliver shallower or more uniform micro-shots, patients report less visible bumps.
  • Good for larger surface areas: If the goal is full-face or large-area rejuvenation, machine method can cover more ground.

⚠️ Trade-offs

  • Less precise: The device may not perfectly adapt to curved or thin areas (under-eye, nose bridge) — risk of product loss or sub-optimal depth.
  • Potential for leakage: Some studies note that machines may cause more drug loss due to suction or depth mismatch.
  • Uniformity may suffer: While wide areas are covered, delicate or nuanced zones may require manual ‘touch-up’.

Which Method Should You Choose?

Here’s how to decide based on your skin condition and goals:

  • Delicate areas / detailed correction (under-eye hollows, thin skin, localized pores): Go with hand injection by an experienced dermatologist for best precision.
  • General skin quality improvement across the full face or neck (texture, fine lines, pores) with minimal downtime: Machine-assisted injection can be efficient and comfortable.
  • Combination approach: Many clinics use a machine for full-face coverage, then hand-inject key zones for refinement — provides the best of both worlds.
  • Be sure your doctor assesses skin thickness, area, prior treatments, and selects the method accordingly.

Aftercare & What to Expect

  • You might see small raised bumps (“embossing”) especially with hand injection — this is normal and shows correct placement.
  • Mild swelling, redness or bruising possible — more so if hand injections are used.
  • Avoid heavy exercise, saunas, and strong skin treatments for 24–48 hours.
  • Hydrate skin well, wear SPF daily, and follow your dermatologist’s maintenance plan.
  • Expect visible improvements in 3–4 weeks, with full effect over several months as collagen and skin repair processes work.

Summary

Both hand and machine delivery methods for Rejuran have their place. If you prioritise precision, detailed areas and maximum efficacy, hand injection is the gold standard — provided the dermatologist is skilled. If you prioritise comfort, speed and broad-area skin boosting, machine delivery may be a good choice. What truly matters is the skill of the injector, the correct dosage, the right depth, and a honest consultation on which method suits your skin and concerns.

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