Salmon DNA skincare refers to PDRN — polydeoxyribonucleotide — a purified fragment of DNA extracted from salmon or trout and used to support skin repair. It is not a filler and it does not add volume. Rather than filling tissue, PDRN is studied for biological effects associated with tissue repair — principally adenosine A2A receptor signalling and the nucleotide salvage pathway — which has led to interest in using it alongside procedures that create controlled injury, such as microneedling and laser.
The ingredient has been studied for more than two decades, mostly in wound healing. Its move into aesthetics is newer, and the evidence there is real but narrower than social media suggests. This guide explains what PDRN is, what the clinical literature actually found, how it is regulated in Canada, and what it cannot do.
Written and clinically reviewed by I. Goldis, R.N., BScN — Lips Boutique® by J.K.A., Toronto. Last reviewed August 2026.
What is PDRN?
PDRN stands for polydeoxyribonucleotide. It is a mixture of DNA fragments of varying chain lengths, purified from the sperm of salmon or trout. Related preparations are called polynucleotides, or PN — the same building blocks in longer chains, which behave slightly differently in the skin.
PDRN and PN are both DNA-derived polynucleotide preparations. In contemporary dermatology literature, PDRN generally refers to shorter or lower-molecular-weight fragments, while PN generally refers to longer, higher-molecular-weight chains. The terminology has not been used consistently across older studies, so the exact formulation studied matters.
- PDRN — generally the shorter fragments, studied primarily for biological signalling effects.
- PN (polynucleotides) — generally the longer chains, which can also contribute to hydration and viscoelasticity depending on the formulation. This is the form most often sold as an injectable abroad, under brand names such as Rejuran®.
Why fish DNA?
Salmon and trout are a consistent, well-characterised source, and the DNA can be purified to pharmaceutical standards at scale. PDRN preparations undergo purification intended to remove proteins, peptides and other potentially immunogenic components, and the resulting fragments are controlled for molecular weight. Tolerability in published studies is generally good, and that appears to owe more to purity, molecular characteristics and manufacturing control than to any simple similarity between fish and human DNA.
Patients with significant fish allergy, or a notable allergy history generally, should still disclose it before treatment. Clinical trials of PDRN have listed allergy to the preparation as an exclusion criterion.
How does salmon DNA work on skin?
Two principal mechanisms have been proposed and extensively studied for PDRN.
First, adenosine A2A receptor signalling. PDRN-associated effects are thought to involve activation of the adenosine A2A pathway. In experimental models, this pathway has been associated with fibroblast activity, collagen-related repair processes and angiogenesis — the formation of new small blood vessels. Squadrito and colleagues set out this pharmacology in Frontiers in Pharmacology (2017), which remains the standard reference for the molecule.
Second, the salvage pathway. The fragments also supply raw nucleotides that cells can reuse to build new DNA without synthesising it from scratch — a metabolic shortcut that matters most when tissue is repairing itself.
A third, less discussed property: PDRN has demonstrated anti-inflammatory effects in experimental models. Noh and colleagues (International Journal of Molecular Sciences, 2016) also documented anti-melanogenesis activity — a dampening of pigment production — in laboratory work. That finding is preclinical and mechanistic; it explains why pigmentation is measured alongside wrinkles in several aesthetic studies, but it does not by itself establish a clinical pigmentation benefit.
What the clinical research shows
Wound healing and scars
PDRN’s deepest evidence base is not cosmetic. A 2026 systematic review in Cureus examined randomised clinical trials of polynucleotides and PDRN across skin rejuvenation, scar prevention and wound healing. Seven randomised trials involving 183 participants met inclusion criteria. Across the included trials, improvements were reported in wrinkle-related outcomes, scar measures and wound-healing outcomes, but the evidence base was small and heterogeneous.
One example from the scar-prevention literature: Kim and colleagues (Advances in Wound Care, 2023; published online 2022) randomised 44 thyroidectomy patients, giving the treatment group PDRN injections on the first and second postoperative days. At three months the treated group showed a significantly lower vascularity subscore on the modified Vancouver Scar Scale, with no specific side effects reported.
Skin rejuvenation — real but smaller
Much of the published aesthetic evidence comes from South Korea, where injectable polynucleotide treatments have been studied and used clinically for skin rejuvenation.
- Split-face polynucleotide study. In a randomised, double-blind split-face trial involving 27 participants, a polynucleotide treatment was compared with non-crosslinked hyaluronic acid for periocular rejuvenation. Investigators assessed outcomes including elasticity, hydration, roughness and dermal density, and reported improvement in several skin-quality measures — although the small sample limits the strength of the conclusions.
- Crow’s feet. Jeong and colleagues (Journal of Cosmetic Dermatology, 2020; PMID 31680395) found polynucleotides comparable to polycaprolactone fillers, with different recovery profiles.
Salmon DNA with microneedling
This is the combination most relevant to clinics outside Asia, and the evidence is newer.
A 2025 randomised controlled trial published in Aesthetic Medicine enrolled 24 women aged 30–50 with moderate wrinkles and facial hyperpigmentation. Participants received either microneedling with PDRN salmon 3% or microneedling with platelet-rich plasma, two sessions three weeks apart. Both groups showed statistically significant improvement from baseline. The PDRN group showed a significantly greater reduction in wrinkle score on the Lemperle scale. On the pigmentation endpoint, however, the difference between PDRN and PRP was not statistically significant — both improved, neither clearly outperformed the other. Side effects were minimal and comparable between groups.
Yogya and colleagues (Dermatology and Therapy, 2022) studied periorbital wrinkles in 30 participants over three RF microneedling sessions at two-week intervals — a useful controlled design because both sides of the face received the same RF microneedling treatment, while polynucleotides were applied to one randomised side and saline to the other.
Why delivery is the whole argument
This is the part most articles skip, and it is the most important thing to understand before spending money.
Intact skin is designed to keep molecules out. The widely cited “500 Dalton rule”, set out by Bos and Meinardi in 2000, holds that compounds much above 500 daltons do not passively cross the stratum corneum in meaningful quantities. Conventional PDRN preparations contain DNA fragments with molecular weights far above that threshold, so a conventional PDRN serum applied to unbroken skin faces a genuine penetration problem. Clinical evidence for topical PDRN applied to intact skin remains much more limited than the literature on injectable or procedure-assisted use.
For conventional high-molecular-weight PDRN, passive penetration through intact skin is expected to be limited. Microneedling and other barrier-disrupting procedures can increase cutaneous delivery of topically applied substances by temporarily altering the skin barrier, which is why PDRN protocols commonly apply it after such a procedure. This does not mean no topical formulation could ever work — formulation science and molecular weight both matter, and lower-molecular-weight preparations are an active area of development. It does mean post-procedure PDRN is a biologically different proposition from applying a conventional PDRN cream to intact skin.
The practical implication: a jar of salmon DNA cream and a clinical microneedling protocol with PDRN are not the same thing, and should not be judged as though they were.
Is salmon DNA legal in Canada?
As of August 2026, we could not identify a Health Canada authorisation for Rejuran® for injectable cosmetic use in Canada. More broadly, clinics should verify that any injectable PDRN or polynucleotide product has specific Health Canada authorisation before offering it.
The position on topical PDRN is more nuanced. Health Canada classifies products based on factors including their composition, the claims made for them, their intended use and their level of action. In its 2026 notice concerning topical products containing human-derived exosomes, extracellular vesicles or human cell-conditioned media, Health Canada stated that products represented for use in ways that facilitate percutaneous absorption, including microneedling, are not consistent with cosmetic classification.
That notice specifically concerns human-derived exosomes, extracellular vesicles and human cell-conditioned media. PDRN is a different material and is not addressed by that notice. The notice therefore should not be interpreted as a specific Health Canada determination on PDRN used with microneedling.
The broader regulatory principle remains relevant: the status of a topical PDRN preparation depends on the specific product, including its composition, claims, intended use and method of administration. A clinic should therefore verify the Canadian regulatory status and intended use of the particular product it uses rather than assuming that all topical PDRN products have the same status.
Patients considering treatment can reasonably ask which product will be used, whether it is topical or injectable, and what Canadian regulatory documentation applies to that product.
The regulatory picture differs internationally. PDRN-based products have regulatory approvals for certain medical indications in countries including Italy and South Korea. These approvals should not be interpreted as Canadian authorisation, or as evidence that every PDRN formulation is approved for cosmetic skin rejuvenation.
Is PDRN safe?
Across the published trials, PDRN has a favourable safety profile. Reported adverse events in the published studies have generally been mild and transient, commonly including injection-site or procedure-related redness, swelling, tenderness and erythema.
It is worth separating two different sources of caution, because most clinic pages blur them.
- Procedure-related. Active infection, significant inflammatory skin disease in the treatment area, impaired wound healing and a history of abnormal scarring may affect suitability for microneedling itself, whatever is applied afterwards. Medication history, including isotretinoin, should be reviewed individually before treatment.
- Absence-of-evidence related. Pregnancy, breastfeeding and some autoimmune conditions are generally treated as reasons to postpone because these groups are excluded from the trials, not because harm from PDRN has been demonstrated. That is a different statement, and an honest clinic will say so.
What salmon DNA cannot do
Being straight about this is more useful than another list of benefits.
- It is not a filler. It adds no volume and will not restore lost facial structure. If the concern is hollowing or contour, PDRN is the wrong tool.
- It is not a substitute for sun protection. No regenerative ingredient outruns ongoing UV damage.
- One session should not be assumed to represent a complete course. Collagen remodelling happens over months. Published protocols vary, and outcomes are commonly assessed weeks to months after treatment.
- The aesthetic evidence base is still thin. Reviewers consistently describe study quality as low to moderate — small samples, heterogeneous formulations, short follow-up and inconsistent endpoints. Regulatory authorisation for cosmetic skin rejuvenation should not be assumed for any given PDRN or polynucleotide product; status varies by product, jurisdiction and intended use.
Regulatory authorisation and clinical evidence answer different questions. The absence of an authorised cosmetic indication means claims about efficacy and permitted use should remain appropriately limited — and any clinic promising guaranteed, filler-level results from salmon DNA is overstating what the science currently supports.
Frequently asked questions
What is a salmon sperm facial?
It is an informal name for treatments using PDRN, a preparation of purified DNA fragments commonly derived from salmon or trout. How PDRN is delivered varies by product and jurisdiction. In Canada, patients should ask which specific product is being used, whether it is topical or injectable, and what regulatory status applies to that product.
How many sessions of PDRN microneedling do I need?
Published protocols vary considerably. The randomised trial comparing microneedling plus PDRN with microneedling plus PRP used two sessions three weeks apart; the RF microneedling study used three sessions at two-week intervals. There is not yet a universally established PDRN treatment schedule. What the studies agree on is that collagen remodelling continues for months after the final session, so results are assessed over a full course rather than after a single visit.
What is the difference between PDRN and exosomes?
Both are regenerative ingredients used in post-procedure protocols, but they are different biology. PDRN is a DNA-derived preparation whose proposed pharmacologic effects include adenosine A2A receptor signalling and nucleotide salvage. Exosomes are extracellular vesicles carrying proteins, lipids and nucleic acids. PDRN has a longer and better-characterised research history. Regulatory status differs and should be confirmed with any clinic before treatment.
Is PDRN better than PRP?
In a head-to-head randomised trial pairing each with microneedling, PDRN produced a significantly greater reduction in wrinkle scores than platelet-rich plasma, with both treatments effective and side effects comparable. That is a single trial of 24 participants — informative, not conclusive.
Can I get Rejuran in Canada?
As of August 2026, we could not identify a Health Canada authorisation for Rejuran® for injectable cosmetic use in Canada. Topical PDRN preparations exist, but regulatory status varies by product, and depends on composition, claims, intended use and method of administration. Ask any clinic which specific product they use, whether it is topical or injectable, and what Canadian regulatory documentation applies to it.
Does salmon DNA help with pigmentation?
Laboratory work has documented anti-melanogenesis activity, and small aesthetic studies pairing microneedling with PDRN have reported reduced facial hyperpigmentation. The evidence is early and the sample sizes are very small.
Does it hurt, and what is the downtime?
With microneedling protocols, most discomfort is associated with the procedure itself, and topical anaesthetic may be used depending on the protocol. Expect redness resembling mild sunburn, typically settling within 24 to 48 hours.
Glossary
Terms used in this article, in plain language.
- PDRN — polydeoxyribonucleotide
- A mixture of short DNA fragments, purified from salmon or trout. Studied for its effects on tissue repair.
- PN — polynucleotides
- The same DNA building blocks in longer chains. Depending on the formulation, the longer chains can also contribute hydration and viscoelasticity on top of the biological effects.
- Nucleotide
- The individual chemical unit that DNA is built from. Chains of nucleotides make up a strand of DNA.
- Adenosine A2A receptor
- A cell-surface receptor involved in regulating processes including inflammation, vascular responses and tissue repair. A2A signalling is one of the proposed pathways through which PDRN exerts biological effects.
- Nucleotide salvage pathway
- A recycling route cells use to build new DNA from ready-made nucleotides rather than making them from scratch. It saves the cell energy, which matters most when tissue is repairing itself.
- Fibroblast
- The cell in the dermis that produces collagen and elastin — the proteins responsible for skin firmness and stretch.
- Angiogenesis
- The formation of new small blood vessels. More blood supply means more oxygen and nutrients reaching healing tissue.
- Anti-melanogenesis
- Reducing the production of melanin, the pigment responsible for dark patches and uneven tone.
- Stratum corneum
- The outermost layer of the skin. Its job is to keep things out, which is why most large molecules cannot pass through intact skin.
- Dalton
- A unit for measuring the weight of a molecule. The rule of thumb in dermatology is that molecules much heavier than 500 daltons do not passively cross intact skin in useful amounts.
- Percutaneous absorption
- Movement of a substance through the skin barrier into deeper skin layers or beyond. The degree and intended significance of absorption can be relevant to how a product is classified, together with factors such as claims, composition and intended use.
- Preclinical
- Research done in the laboratory — in cells or in animals — before human trials. Useful for understanding mechanism, but not proof of a clinical result in people.
- Randomised controlled trial (RCT)
- A study in which participants are assigned to treatment or comparison groups by chance, so the groups are otherwise similar. The most reliable single study design for testing whether a treatment works.
- Split-face study
- A trial in which one side of a participant’s face receives the treatment and the other side receives a comparison or placebo. Each person acts as their own control, which removes a lot of variability.
- Systematic review
- A structured survey of all the studies meeting set criteria on a question, assessing them together rather than relying on any single trial.
- Endpoint
- The specific outcome a study set out to measure — wrinkle score, elasticity, pigmentation. A treatment can improve one endpoint and not another.
- Statistically significant
- A result unlikely to be explained by chance alone. It does not mean the difference is large, or that a patient would necessarily notice it.
- Contraindication
- A reason not to have a treatment, or to postpone it.
References
- Squadrito F, Bitto A, Irrera N, et al. Pharmacological activity and clinical use of PDRN. Frontiers in Pharmacology. 2017;8:224. doi:10.3389/fphar.2017.00224
- Colangelo MT, Galli C, Guizzardi S. Polydeoxyribonucleotide regulation of inflammation. Advances in Wound Care. 2020;9(10):576–589. doi:10.1089/wound.2019.1031
- Noh TK, Chung BY, Kim SY, et al. Novel anti-melanogenesis properties of polydeoxyribonucleotide. International Journal of Molecular Sciences. 2016;17(9):1448. doi:10.3390/ijms17091448
- Kim BR, Kwon SH, Kim JW, et al. Early postoperative injections of polydeoxyribonucleotide prevent hypertrophic scarring after thyroidectomy: a randomized controlled trial. Advances in Wound Care. 2023. doi:10.1089/wound.2022.0025 · PMID 35713247 · NCT05149118
- Altavilla D, Bitto A, Polito F, et al. Polydeoxyribonucleotide (PDRN): a safe approach to induce therapeutic angiogenesis in peripheral artery occlusive disease and in diabetic foot ulcers. Cardiovascular & Hematological Agents in Medicinal Chemistry. 2009;7(4):313–321. doi:10.2174/187152509789541909
- Polito F, Bitto A, Galeano M, et al. Polydeoxyribonucleotide restores blood flow in an experimental model of ischemic skin flaps. Journal of Vascular Surgery. 2012;55(2):479–488. doi:10.1016/j.jvs.2011.07.083
- Lee YJ, Kim HT, Lee YJ, et al. Comparison of the effects of polynucleotide and hyaluronic acid fillers on periocular rejuvenation: a randomized, double-blind, split-face trial. Journal of Dermatological Treatment. 2022;33(1):254–260. doi:10.1080/09546634.2020.1748857 · PMID 32248707
- Jeong GJ, et al. Comparison of polynucleotide and polycaprolactone filler for crow’s feet. Journal of Cosmetic Dermatology. 2020. PMID 31680395
- Yogya Y, Wanitphakdeedecha R, Wongdama S, et al. Efficacy and safety of using noninsulated microneedle radiofrequency alone versus in combination with polynucleotides for treatment of periorbital wrinkles. Dermatology and Therapy (Heidelberg). 2022;12:1133–1145. doi:10.1007/s13555-022-00729-7
- Vera V, Praharsini IGAA, Darwinata AE, et al. Comparison of microneedling and polydeoxyribonucleotide salmon 3% versus microneedling and platelet rich plasma in treating wrinkles and facial hyperpigmentation. Aesthetic Medicine. 2025;11(2):16753.
- Alhussain AM, Albusayys STM, Alfhadi MA, et al. Polynucleotides and polydeoxyribonucleotides for skin rejuvenation, postoperative scar prevention, and wound healing: a systematic review of randomized clinical trials. Cureus. 2026;18(7):e112403. doi:10.7759/cureus.112403 · PMID 42572627 · PMCID PMC13453133
- Bos JD, Meinardi MMHM. The 500 Dalton rule for the skin penetration of chemical compounds and drugs. Experimental Dermatology. 2000;9(3):165–169. doi:10.1034/j.1600-0625.2000.009003165.x · PMID 10839713
- Health Canada. Classification of topical products containing human-derived exosomes, human extracellular vesicles, or human cell-conditioned media: Final notice. 2026.
- Health Canada. Guidance document: Classification of products at the cosmetic-drug interface.
Where a study is listed without full author detail, the identifier given (PMID, DOI or PMCID) locates the original publication. Readers are encouraged to consult the primary sources rather than rely on this summary.
About the author
I. Goldis, R.N., BScN is the lead injector at Lips Boutique® by J.K.A. in midtown Toronto. A Registered Nurse with 18 years in medical aesthetics, she focuses on advanced injectables, facial balancing, regenerative therapies and hair restoration. She writes about new treatments as they arrive in Canada — including what the evidence supports and what it does not yet.
Disclosure
Lips Boutique® by J.K.A. is a medical aesthetics clinic and provides treatments discussed in this article, including microneedling with topical PDRN. Readers should weigh that commercial interest when considering the information here.
This article is general education about a treatment category. It is not medical advice, not an advertisement for a specific product, and not a recommendation for any individual. It does not promise or guarantee any result. Treatments are provided by regulated health professionals following individual assessment, and suitability, risks and expected outcomes are determined at that assessment — not from an article.
As of August 2026, we could not identify a Health Canada authorisation for Rejuran® for injectable cosmetic use in Canada. Regulatory status varies by product and intended use, and nothing in this article should be interpreted as claiming Health Canada authorisation for a PDRN or polynucleotide product or indication where none exists.
Written and clinically reviewed by I. Goldis, R.N., BScN, a Registered Nurse in the province of Ontario. No fee or consideration was received from any manufacturer for the content of this article.
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