Polynucleotides (PN) have become one of the most widely discussed injectable biorevitalisers in UK aesthetic practice. A 2025 systematic review in the Journal of Cosmetic Dermatology covering nine published studies and 219 patients found consistent improvements in skin hydration, elasticity and texture, with a favourable safety profile across all included trials. The evidence base is not yet at the level of the hyaluronic acid literature, but it is no longer limited to brand-funded data or single-centre case reports.
What polynucleotides are
Polynucleotides are purified DNA fragments derived, in most commercial formulations, from the gonads of salmon or trout. The material undergoes extensive purification to remove proteins and other immunogenic compounds, leaving nucleotide chains that the body can absorb and metabolise without triggering an immune response.
Two related terms appear across the published literature:
- PN (polynucleotides): longer DNA strand chains
- PDRN (polydeoxyribonucleotides): typically shorter fragments
Both act primarily through the adenosine A2A receptor, though differences in molecular weight may influence receptor binding and downstream effect. The two terms are sometimes used interchangeably in clinical contexts, but they are not identical products and direct comparison between trial results requires care.
PDRN wound-healing preparations have been licensed and used in South Korea for over two decades. That established safety and prescribing record underpins much of the confidence now applied to injectable aesthetic formulations.
How polynucleotides act on skin tissue
The primary mechanism is adenosine A2A receptor activation. Through this pathway, polynucleotides promote:
- Fibroblast proliferation
- Collagen synthesis
- Anti-inflammatory signalling
- Angiogenesis (new blood vessel formation)
The net effect is tissue stimulation rather than volumisation. This distinguishes PN clearly from hyaluronic acid fillers, which work through physical water binding and volume replacement. In aesthetic practice, polynucleotides are generally positioned as regenerative treatments aimed at improving underlying tissue quality rather than correcting visible loss.
Across published studies, outcomes include improved dermal hydration (measured by corneometry), better skin elasticity (cutometry), reduction in fine lines, improved texture and pore appearance, and reduction in periorbital rhytides. The quality of the evidence underpinning each of these outcomes varies, which is why the systematic review is worth reading carefully.
What the systematic review found
The Lampridou et al. review, published in 2025 in the Journal of Cosmetic Dermatology, is the most comprehensive published synthesis of the PN evidence to date. Searches covered Embase, Medline and the Cochrane Library from January 2010 to January 2024. Nine studies met inclusion criteria, across a combined population of 219 patients.
Across all nine studies, polynucleotide treatment produced measurable improvements in skin quality outcomes. The consistency of direction across a heterogeneous set of trials is meaningful. An effect that appears in every study, across different patient populations and product formulations, carries more weight than a single well-designed trial with a narrow sample.
The authors rated study quality as low to moderate. Common limitations included small sample sizes, lack of blinding, short follow-up periods, and variability in the PN products used. That last limitation matters practically. Different commercial formulations vary in molecular weight, concentration, purification standard and vehicle. Results from a trial using one product cannot be assumed to translate automatically to a different formulation.
Serious adverse events were not reported across any of the included studies. Local reactions at injection sites (swelling, erythema, bruising) were consistent with those seen from other intradermal injectables.
The honest summary: the direction of effect is consistent and the safety profile is reassuring, but the literature would benefit from larger, blinded, randomised controlled trials with standardised formulations.
Real-world clinical data
Alongside controlled trials, real-world data are accumulating. A clinical assessment published in the Journal of Cosmetic Dermatology evaluated practitioner-rated outcomes across facial, neck and décolleté treatments using a high-purification PN formulation.
Clinician-rated outcomes showed visible improvement in 100% of facial cases. Over 53% were rated as "marked" or "excellent". Neck and décolleté results showed moderate to significant improvement in the majority of cases.
Real-world datasets are not controlled trials. Selection bias, the absence of blinding, and the absence of a control group limit what can be concluded about efficacy in isolation. What they offer is a safety signal at scale, a practitioner perspective on practical tolerability, and patient-reported satisfaction in everyday clinical conditions. On those counts, PN continues to perform well.
A 2026 prospective study added validated patient-reported outcomes via the FACE-Q questionnaire for periorbital treatment, with assessments at one, three and six months. Patient-reported improvement in periorbital appearance was sustained through the six-month endpoint. For practitioners working in the periorbital region, where volumising fillers carry greater anatomical risk, this duration of effect is clinically relevant to treatment planning.
Emerging evidence: acne scarring
One area where PN evidence has moved quickly is atrophic acne scarring. Controlled data now show that specific PN formulations produced significant improvement in moderate to severe atrophic acne scars in adult women compared to placebo. For practitioners working with acne presentations and building a full clinical toolkit that includes injectable adjuncts, this is an evidence signal worth tracking. The clinical decision-making framework for complex acne cases, including when injectable options are appropriate, is covered in depth in Acne Decoded.
What practitioners need to consider before adding PN
Practitioners adding or reviewing polynucleotides in their clinic should look past brand marketing to the underlying clinical data for the specific product under consideration. Key questions to ask:
- What is the molecular weight and concentration of this formulation?
- What purification standard does the manufacturer apply?
- Is there published evidence specifically for this product?
- What is the regulatory status of this product in the UK?
That last point is not an administrative detail. Injectable polynucleotides in the UK sit within the medicines regulatory framework. Prescribers need to confirm the licensed or unlicensed status of any specific product before introducing it to practice, and apply the standard prescribing, consent and record-keeping obligations that apply to all injectable medicines.
JCCP standards require that practitioners use only products and techniques for which there is a credible evidence base. The growing PN literature means that requirement is increasingly met, but reading the evidence critically remains the practitioner's responsibility.
For a structured programme that places evidence-led clinical decision-making within a UK regulatory framework, the Aesthetics Unlocked course catalogue covers both the clinical and regulatory foundations that underpin decisions of this kind.
FAQ
Are polynucleotide injectables evidence-based?
A 2025 systematic review in the Journal of Cosmetic Dermatology analysed nine studies covering 219 patients and found consistent improvement in skin hydration, elasticity and texture across all included trials. Study quality was rated low to moderate, and the literature lacks large, blinded randomised controlled trials. The direction of effect is consistent; the evidence base is growing.
Are PN and PDRN the same thing?
Not exactly. Both are purified DNA-derived fragments acting primarily through the adenosine A2A receptor. PN typically refers to longer chains; PDRN to shorter fragments. The molecular weight difference may affect receptor binding and clinical effect. The terms appear interchangeably in some contexts, which can make direct comparison between studies difficult.
Are polynucleotide injectables safe?
Across published studies, serious adverse events have not been reported. Local reactions at injection sites including swelling, erythema and bruising were consistent with those from other intradermal injectables. Long-term safety data beyond six to twelve months remain limited in the peer-reviewed literature.
Do polynucleotides replace hyaluronic acid fillers?
No. They work through different mechanisms and serve different clinical objectives. Hyaluronic acid provides immediate volumisation through water binding. Polynucleotides stimulate tissue repair via receptor-mediated pathways. In clinical practice they are typically used alongside each other, not as alternatives.
Are polynucleotide injectables regulated as medicines in the UK?
Injectable polynucleotides sit within the UK medicines regulatory framework. Practitioners should confirm the regulatory status of any specific product they intend to use. JCCP standards require injectable treatments to be carried out under appropriate prescribing arrangements, with adequate clinical evidence and full patient consent documentation in place.