PDRN vs PN: What's the Difference Between Salmon DNA Treatments?

PDRN and PN are both made from purified salmon DNA, but they differ mainly in the length and size of the DNA fragments. PDRN (polydeoxyribonucleotide) is made of shorter, lighter fragments and is a thin, watery liquid that spreads easily and is often used for a gentle regenerative and soothing effect. PN (polynucleotide) is made of longer chains, forming a thicker gel that stays in the skin longer and is thought to offer more structural support as well as repair. In practice, PN is often chosen for texture, thin skin and fine lines, while PDRN is commonly used for skin recovery, sensitivity and as a lighter booster. Both are considered generally safe, and evidence for both is promising but still limited.

This article explains the differences in more detail and how doctors decide which one may suit you.

Where Both Come From

Both PDRN and PN are extracted from the reproductive cells of fish, most often salmon or trout. The DNA is purified to remove proteins and impurities that might cause reactions. After purification, manufacturers process the DNA to different sizes, which is what creates the distinction between the two ingredients.

Neither ingredient contains living cells, and neither alters your own DNA. Both act locally in the skin and are gradually broken down by the body. Both have also been used in other areas of medicine, such as wound healing, before becoming popular in aesthetics.

The Key Difference: Fragment Size

The simplest way to understand the difference is to think of fragment length:

• PDRN: shorter fragments with a lower molecular weight. The product is fluid and absorbs quickly.
• PN: longer fragments with a higher molecular weight. The product is more viscous and gel-like, and tends to remain in the tissue longer.

This difference in size affects how the products behave once injected. PDRN is thought to act mainly through biological signalling that supports cell repair and reduces inflammation. PN is believed to share these effects while also providing a kind of temporary scaffold that may support the skin's structure and hydration for longer.

These explanations are based on laboratory research and clinical experience. Direct head-to-head studies comparing PDRN and PN for cosmetic results are limited, so the practical differences are partly based on expert opinion.

How They Compare in Practice

Doctors often consider the following general differences:

• Texture: PDRN is lighter and runnier; PN is thicker.
• Feel of treatment: PN injections can be more uncomfortable and may leave more noticeable bumps. PDRN is often described as gentler.
• Downtime: both usually involve small bumps and redness, but PDRN bumps may settle a little faster.
• Main goals: PDRN is often used for soothing, recovery and a mild glow. PN is often chosen for thin, crepey or ageing skin and fine lines.
• Delivery: PDRN is often combined with microneedling or applied after laser treatments, as well as injected. PN is typically injected.

When PDRN Might Be Chosen

PDRN may be suggested when the main aim is to calm and support skin, for example:

• Sensitive or reactive skin that needs gentle repair
• Recovery after lasers, peels or other procedures
• Dull, tired-looking skin in younger people without significant ageing
• As an introduction to skin boosters for someone wary of more intense treatments

PDRN is also found in some topical skincare products. These are different from injections, and evidence for how much topical PDRN penetrates the skin is limited, so their effects are likely to be milder.

When PN Might Be Chosen

PN may be recommended when there is a need for more noticeable improvement in skin quality, such as:

• Thin or crepey skin, including under the eyes or on the neck
• Fine lines and loss of elasticity
• Rough texture and enlarged-looking pores
• Shallow acne scars, usually alongside other treatments

Rejuran, developed in Korea, is the best-known PN brand, with versions for the face, eyes and scars. Other PN products are available in Korea and elsewhere.

Safety and Side Effects

Both PDRN and PN are generally considered well tolerated when used by trained practitioners. Common side effects include:

• Small bumps at injection points
• Redness and mild swelling
• Bruising
• Tenderness

Less common risks include infection, persistent lumps and allergic reactions. Tell your doctor about any fish allergy, pregnancy or breastfeeding, skin infections, autoimmune conditions or medicines that affect bleeding. Ask which product is being used and make sure it is from a reputable source, since product quality matters.

Can They Be Combined?

Some clinics use PDRN and PN at different stages of a treatment plan, or combine one of them with hyaluronic acid boosters, lasers or energy-based devices. For example, PDRN might be used to support recovery after a laser session, while PN might be used in a course to improve thin skin. Combinations can be useful, but there is limited high-quality evidence on the best sequences, so plans tend to be based on the doctor's experience and your skin's needs.

If you are visiting Korea, where both types of treatment are widely available, ask your doctor to explain which product is being used and why, and keep a record for any future treatment at home.

Frequently asked questions

Is PN stronger than PDRN?

"Stronger" is not quite the right word. PN is thicker and may last longer in the skin, while PDRN is lighter. Which is better depends on your goals.

Are both made from salmon?

Usually, yes. Both are generally derived from purified salmon or trout DNA, processed to different fragment sizes.

Which one has less downtime?

PDRN is often considered gentler, with bumps that may settle slightly faster, but both usually involve only short downtime.

Do PDRN skincare products work like injections?

Not in the same way. Topical products are likely to have milder effects because penetration into the skin is limited.

Personalised Advice

PDRN and PN are related but not identical, and the right choice depends on your skin condition, goals and tolerance for downtime. A qualified dermatologist can assess your skin and recommend whether either, both or a different approach is best for you.