PDRN and Salmon DNA
About PDRN and Salmon DNA
PDRN, short for polydeoxyribonucleotide, and its close relative PN, or polynucleotides, are injectable skin treatments made from long chains of DNA extracted from salmon. Before it reaches a clinic, the DNA goes through careful cleaning and purification and is made sterile. The two are not quite identical: PN is taken from the testes of the fish and is made of longer, heavier chains, while PDRN comes from the sperm cells, so each acts a little differently in the skin. Both are often called skin boosters or, informally, salmon DNA treatments. Tiny amounts are placed into the skin with a very fine needle or a cannula, most often on the face, under the eyes, on the neck and on the hands. They are thought to support skin repair by stimulating the cells that make collagen and by calming inflammation, with the aim of improving texture, fine lines, hydration and overall skin quality. It is important to know that this mechanism is not yet fully proven in people. Some products combine PN with hyaluronic acid. A typical course is two or three sessions spaced around two weeks apart, with the appointment length depending on the areas treated and the numbing time needed. Topical skincare products containing PDRN are also sold, but these are not the same as injections.
On the day, and after
During the treatment
Your practitioner will check your medical history, take photographs and ask you to sign a consent form once you understand the possible side effects. Your skin is cleansed thoroughly, and a numbing cream is often applied and left to work before treatment starts, particularly for the delicate under-eye area. The product is then placed in very small amounts, either as a series of tiny injections with a fine needle or through a blunt cannula, depending on the area and your practitioner's technique. You will see small raised bumps along the treated skin, which is expected. A careful practitioner works steadily, watches your skin throughout and tells you what they are doing as they go. The injecting itself is usually fairly quick. Afterwards the area is cleaned and you receive written aftercare advice, a plan for your next session and a contact number for any concerns.
How it feels
Most people find polynucleotide injections uncomfortable rather than painful, especially with numbing cream applied first. You will feel a series of small scratches or pinches as the needle enters the skin, and a brief stinging or pressure as the product goes in. Some areas, such as under the eyes or around the mouth, tend to feel more sensitive than others. If a cannula is used, you may feel a pushing or gliding sensation rather than repeated pricks. Straight afterwards, the treated skin may feel slightly raised, warm or tender, and you may see small bumps. These usually settle within hours to a day or two. Pain that is severe, worsening or spreading, or any change in skin colour, is not expected and should be reported to your practitioner promptly.
Results and maintenance
Polynucleotide treatments work gradually rather than giving an instant change. A typical course is two or three sessions spaced around two weeks apart, and practitioners say the improvement tends to hold for somewhere between six months and a year, when a top up may be offered. It is important to keep expectations balanced. Reviews of the research describe a scarcity of high-quality, large randomised trials, with most evidence coming from small studies, case series and expert opinion, and the way polynucleotides work in human skin has not been objectively demonstrated. In 2026, practitioners have called for independent studies with objective outcome measures and longer follow-up. Serious adverse events have not been reported in the studies reviewed, which is reassuring, but it is not the same as long-term proof. Daily sunscreen and a good skincare routine support whatever improvement you see.
Before and after your appointment
Before your appointment
Begin with a face-to-face consultation, where your practitioner looks at your skin, takes a full medical history and explains what polynucleotides can and cannot do. Tell them straight away if you have any fish or shellfish allergy, as this is a reason not to go ahead. Let them know if you are pregnant, breastfeeding or planning a pregnancy, and about any autoimmune condition, bleeding disorder or medicines that thin the blood, such as aspirin, ibuprofen or warfarin. Supplements including fish oil, ginkgo, vitamin E and St John's wort can also increase bruising. Never stop a prescribed medicine without speaking to the doctor who prescribed it. Postpone if you have an infection, cold sore or rash in the treatment area, or feel unwell. Arrive with clean skin, and plan around any events, since small bumps and bruising are possible. Ask your practitioner which product they use and how it is classified.
Aftercare
Expect some redness, small bumps and possibly a little swelling or bruising at first. These usually settle within hours to a couple of days. Keep the area clean and avoid touching or pressing it. Your practitioner will give you aftercare specific to the product used, so follow their advice closely, and ask in particular how long to wait before wearing make-up, exercising hard, drinking alcohol or using a sauna, steam room or hot tub, as timings can differ between products and practitioners. If you bruise easily, ask how best to manage it. Protect your skin with a high factor sunscreen every day. Contact your clinic promptly if redness, swelling or pain gets worse rather than better, if any area turns pale or mottled, or if you notice itching, hives or swelling away from the treatment site. Lumps or swelling that appear weeks or months later should also be reported, as delayed reactions can occasionally occur.
Downtime is usually short, and most people return to work the same day or the next. Redness, small bumps and mild swelling typically settle within hours to a couple of days. Bruising is possible, especially under the eyes, and can take a few days to fade, so leave a week or more before an important event if you can. Follow your practitioner's guidance on when to return to exercise, alcohol, make-up and heat, as this varies between products. Recovery follows the same pattern after each session in your course. Report any swelling or lumps that appear weeks or months afterwards, as these need assessment.
Safety and medical considerations
Safety essentials
In many countries, rules on who can provide polynucleotide injections are tightening, and some places require practitioners to hold a licence or be medically qualified, while others have no licensing scheme yet. Check the rules where you live. Professional guidance advises that injectable treatments should only be given by appropriately trained healthcare professionals, ideally a regulated professional on a recognised professional body or accredited register. Products vary, so ask whether yours is a prescription only medicine. If it is, it must be prescribed by a prescriber after a face-to-face consultation with you, and in many countries it should not be advertised to the public. Experienced practitioners suggest confirming that the product is authorised for the way it is being used and that the manufacturer can point to solid evidence behind it. Your practitioner should hold insurance that names the treatment, work in clean clinical premises with single use needles, and know how to manage complications.
Medical considerations
If you are allergic to fish or shellfish, this treatment is not for you, because purification does not remove every chance of an allergic response. They are generally avoided during pregnancy and breastfeeding, because there is not enough evidence to show they are safe. With an autoimmune condition such as lupus or scleroderma, your practitioner may steer away from blends that include hyaluronic acid, as there is a possible, though unproven, chance it could set off a flare. Bleeding disorders and blood thinning medicines increase bruising, and any current infection near the treatment site, including shingles or cellulitis, is a reason to postpone. Tell your practitioner about any recent cosmetic treatments too. Seek prompt advice if you notice worsening pain, skin turning pale or mottled, spreading redness or swelling. Delayed reactions, usually linked to hyaluronic acid in combination products, can appear months later and need assessment by a prescriber. For difficulty breathing or swelling of the face or tongue, call your local emergency number straight away.
Patch testing
A patch test is not routinely carried out before polynucleotide injections, and it is not a way to make treatment safe for someone with a fish allergy. Clinical guidance rules out PN and PDRN injections for anyone allergic to fish or shellfish: the material comes from salmon, and even highly purified product cannot be guaranteed reaction free. Allergies to salmon DNA are described as rare, and some clinicians suggest a patch test for people with very sensitive skin or a history of seafood related reactions, so it is worth discussing with your practitioner if this applies to you. Most importantly, your practitioner should screen you carefully at consultation, asking about food allergies, previous reactions to injectables, skin conditions and any reaction to numbing creams. If your product also contains hyaluronic acid, ask about that too, since delayed reactions are more often linked to that ingredient. Allow time for this conversation well before your treatment day, so that you can decide without pressure.
Knowing a good practitioner
Green flags
A reassuring clinic starts with a thorough consultation that covers your medical history in detail, including fish and shellfish allergies, pregnancy, autoimmune conditions and medicines. Your practitioner is a regulated healthcare professional, happy for you to check their registration, and may appear on a recognised accredited register. They name the product, explain whether it contains hyaluronic acid, tell you how it is classified and, if a prescription is needed, who the prescriber is. They are honest that the evidence is still developing and describe benefits in measured terms. Training from the manufacturer and support for complications are in place. The room is clean and clinical, needles are single use and consent is written. You leave with aftercare advice, a contact number and a clear plan for your course, and you are welcome to take time to think before booking.
Red flags
Take a step back if the person injecting cannot show you a professional registration you can check, or if no consultation takes place before treatment. Be cautious of anyone who does not ask about fish or shellfish allergies, as this is one of the most important questions for this treatment. Claims that salmon DNA will regenerate or restore your skin, or promises of dramatic results, go beyond the current evidence. Unnamed products, packaging you are not allowed to see, and treatment in a home without a clinical room or at a social event are concerns. Pressure to buy a large course on the spot, vague answers about side effects and no aftercare contact all suggest the clinic may not support you if something goes wrong.
Questions to ask
At your consultation, ask what your practitioner's professional background is and which register you can check them on. Find out which product they use, whether it contains hyaluronic acid and whether it is a prescription only medicine, and if so who prescribes it. Ask what evidence supports it for your concern and what result is realistic for your skin. It is worth asking how they screen for fish allergy, how they manage reactions, and whether their insurance covers this treatment. Finally, ask how many sessions they recommend.
Frequently asked questions
What is salmon DNA skin treatment?
It is an injectable skin booster made from purified DNA fragments taken from salmon, known as PDRN or polynucleotides. It is placed in tiny amounts into the skin to support skin quality, hydration and fine lines. Results build gradually over a course of sessions, and the evidence is promising but still limited.
Does PDRN actually work?
Some studies report improvements in skin quality, but reviewers describe the evidence as limited, with few large, high-quality trials and most data from small studies or expert opinion. How it works in human skin has not been objectively shown. A good practitioner will describe the potential benefits honestly and help you set realistic expectations.
Can I have polynucleotides if I am allergic to fish?
No. Clinical guidance rules these injections out for anyone allergic to fish or shellfish, since they come from salmon and purification cannot remove every chance of a reaction. Tell your practitioner about any food allergies at your consultation, and ask about alternative treatments that may suit you.
How many polynucleotide sessions do I need?
A typical course is two or three sessions spaced around two weeks apart, though your practitioner will tailor this to your skin and the area treated. Results are reported to last around 6 to 12 months, after which a top up may be suggested. Ask your practitioner what plan they recommend for you.
Are PDRN serums the same as injections?
No. Topical skincare products containing PDRN are applied to the surface of the skin and are regulated differently from injectable products, which are placed into the skin by a practitioner. They are not interchangeable, and results from injection studies cannot be assumed to apply to creams or serums.
This guide is general information, not medical advice. Speak to a qualified practitioner, and to your GP if you have a medical condition, before booking.