Rejuran Healer has become a cornerstone of regenerative medicine in 2026, prized for its ability to repair skin using salmon-derived polynucleotides (PN). While its bio-compatible nature makes it highly safe, understanding the “downtime” and potential reactions is essential for a smooth recovery.
At Her Clinic Malaysia, LCP-certified doctors specialize in Rejuran treatment, using our expert analysis to craft personalized protocols that ensure a natural, glowing, and youthful transformation.
Rejuran Side Effects Explained
What Are Rejuran Side Effects?
Rejuran side effects are typically localized skin reactions resulting from the injection process rather than the product itself. Because PN is highly compatible with human DNA, systemic “allergic” reactions to the substance are rare; most side effects are related to the mechanical trauma of the needles.
Why Side Effects Can Occur After Rejuran
The Rejuran serum is relatively viscous (thick). When injected into the superficial dermis, it takes time to be absorbed into the surrounding tissue. This physical displacement of skin layers, combined with multiple micro-injections, triggers a natural inflammatory response.
Common Rejuran Side Effects
Redness and Swelling After Rejuran
Almost every patient experiences erythema (redness) and mild swelling immediately following the procedure. This is your skin’s way of responding to the micro-trauma and is a sign that the healing cascade has been activated.
Injection Bumps and Skin Texture Changes
Often called “mosquito bites,” these small raised bumps are the most distinct Rejuran side effect. They occur because the PN gel sits in the skin until it is fully absorbed. These are a normal part of the treatment and indicate the product was placed at the correct depth.
Mild Pain or Tenderness at Injection Sites
Rejuran is known to be slightly more “stinging” during injection than hyaluronic acid fillers. After the numbing cream wears off, you may feel a dull tenderness or a “tight” sensation for a few hours.
Bruising as a Rejuran Side Effect
Since the procedure involves many tiny injections, hitting a small capillary is possible. Bruising is more common in sensitive areas like the under-eyes or if you have recently taken blood thinners like aspirin.
Rejuran Side Effects Timeline
| Timeline | What to Expect |
| 0–24 Hours | Visible bumps, redness, and mild swelling. Skin may feel hot. |
| 24–48 Hours | Bumps begin to flatten; redness fades to a pinkish hue. |
| 3–7 Days | Most marks disappear. Any bruising may turn yellow before fading. |
| 7+ Days | Skin texture normalizes; the “glow” begins to manifest. |
Rejuran Side Effects in the First 24–48 Hours
This is the peak of the “downtime.” The bumps are most prominent during this window. It is recommended to avoid social events during the first two days if you are concerned about the visible “grid” pattern on your face.
Rejuran Side Effects After 3–7 Days
By the third day, most bumps have dissolved. You might experience some minor skin flaking or dryness as the injection sites heal.
When Rejuran Side Effects Typically Resolve
For the majority of patients, all visible side effects resolve within 3 to 5 days. If you have very thin or sensitive skin, it may take up to a full week.
Less Common Rejuran Side Effects
Prolonged Swelling or Redness: If swelling persists beyond 4 days, it may be due to a particularly aggressive injection technique or high skin sensitivity.
Itching or Skin Sensitivity: A mild “tight” or itchy feeling can occur as the skin heals.
Uneven Skin Texture: Occasionally, some areas may absorb the product slower than others, leading to a temporary “lumpy” feeling that resolves within a week.
Rare but Serious Rejuran Side Effects
Signs of Infection After Rejuran
Infection is extremely rare but possible if the skin wasn’t cleaned properly or if you touch the injection sites with dirty hands. Watch for:
Increasing pain after 48 hours.
Pus or yellow crusting.
Fever or localized heat.
Allergic Reactions and Hypersensitivity
While Rejuran is bio-compatible, those with severe seafood allergies should exercise caution, as the DNA is sourced from salmon.
When to Seek Medical Attention
Contact your provider immediately if you experience shortness of breath, severe facial swelling away from the injection site, or if the skin turns a mottled “dusky” purple color.
Factors That Affect Rejuran Side Effects
Skin Type and Sensitivity: Thin, fair skin tends to show redness and bruising more prominently.
Injection Technique: Hand-injected Rejuran usually results in more visible bumps than injector-gun methods, though many providers prefer hand-injections for better precision.
Number of Sessions: Cumulative treatments strengthen the skin barrier, often making side effects milder in subsequent sessions.
How to Reduce the Risk of Rejuran Side Effects
Pre-Treatment Guidelines
Avoid Blood Thinners: Stop taking fish oil, Vitamin E, NSAIDs (like Ibuprofen), and alcohol 3–5 days before.
Hydrate: Well-hydrated skin heals faster.
Post-Treatment Care to Minimize Side Effects
Hands Off: Do not touch or massage the bumps; let them absorb naturally.
Stay Cool: Avoid saunas, steam rooms, and vigorous exercise for 48 hours.
Sun Protection: Use a physical sunscreen to prevent post-inflammatory hyperpigmentation at the injection sites.
Rejuran Side Effects vs Normal Healing Responses
What Is Normal vs Abnormal After Rejuran
Normal: Bumps that look like small hives, pinkness, and slight tenderness.
Abnormal: Extreme pain, spreading rashes, or bumps that get larger after day 3.
How Long Normal Side Effects Should Last
Standard side effects should never last more than 7 to 10 days. If you are still seeing “bumps” after two weeks, consult your practitioner to ensure the product was placed correctly.
FAQs About Rejuran Side Effects
Are Rejuran Side Effects Permanent?
No. The bumps and redness are temporary physiological responses to the injection and the PN gel.
Are Rejuran Side Effects Painful?
Most patients describe the recovery as “uncomfortable” or “tender” rather than painful.
Can Rejuran Side Effects Worsen Over Time?
No. Side effects should peak within the first 24 hours and improve daily thereafter.
Summary of Rejuran Side Effects and Safety Considerations
Rejuran is a highly safe, FDA-approved (in many regions) treatment for skin rejuvenation. While the “mosquito bite” bumps and temporary redness can be startling, they are a normal part of the process. By choosing a qualified provider and following post-care instructions, you can minimize downtime and enjoy the long-term regenerative benefits of PN therapy.
