Does Topical PDRN Work? A Korean Doctor Explains

Following my last post on basic skincare tips from Korean beauty nerds on TheQoo (https://www.reddit.com/r/KoreanBeauty/comments/1w6116w/what_korean_beauty_nerds_have_been_saying_about/) this time, I wanted to talk about PDRN.

The PDRN hype may have died down a little, but I still see so many skincare products being marketed around PDRN and related ingredients.

And honestly, why do we always have to fall for marketing?

I’m so tired of the whole cycle of buying skincare that either doesn’t suit my skin or doesn’t really do anything, only to spend even more time and money trying to get my skin back to where it was.

As a Korean, I just hope that the little bit of information I can share from this side of the K-beauty world might be helpful to some of you.

There’s a Korean doctor on YouTube who made a really good video about PDRN, and I’m guessing it’s probably not very well known outside Korea. So I translated the main points and brought them here, along with some added explanations and context to make things easier to follow.

To make things easier to understand, I may simplify some of the scientific mechanisms or explanations along the way. I’ll also add some of my own thoughts or extra context in parentheses.

So please keep that in mind while reading, and as always, take whatever you find useful and leave the rest :)

This is the original video:
https://www.youtube.com/watch?v=f8qucCqnpOw

If you understand Korean well, you might want to check it out yourself too.

Conclusion

For PDRN to actually do what it’s supposed to do, it needs to get past the stratum corneum and reach the dermis. But topical PDRN can’t really get through the stratum corneum — basically, the skin barrier — so the effect is minimal.

Here’s the translation:

Video summary / translation

What PDRN is and why it has to reach the dermis 00:00–03:30

These days, I’ve been seeing a lot of PDRN creams and serums at Olive Young, so today I wanted to talk about something that may be a little less positive.

One of the big questions in dermatology is: how can we increase collagen regeneration in the dermis?

(Collagen makes up around 70–80% of the dermis. I like to think of it as the structural reinforcement and “glue” of our skin. It helps support many of the things people usually want from skincare — firmer-looking skin, the appearance of smaller pores, and better structural support for hydration. Basically, a lot of what people associate with that smooth, “glass skin” look.)

When DNA fragments are delivered into the dermis, they can help support collagen regeneration.

These DNA-derived materials are commonly extracted from salmon. One reason salmon is often used is that its DNA is said to be highly similar to human DNA, which helps reduce the chance of an immune reaction in the skin. (Simply put, PN and PDRN are purified fragments of DNA. They’re made from similar material, but one of the main differences is their size — PN is generally larger and made up of longer DNA chains.

Because of that, PN may stay in the dermis longer, which could allow it to have a greater effect on collagen production.)

When PN is injected directly into the dermis, it basically signals to the skin that it’s time to repair itself, which can help stimulate collagen synthesis. (This is essentially the idea behind Rejuran treatments.)

Why topical PDRN cannot get through the skin barrier 03:31–04:24

The problem is, PN needs to get past the outer layer of the skin and reach the dermis in order to actually do anything.

And whether you spend $100 or $1,000 on a skincare product, the skin barrier generally does not allow molecules larger than around 500 Da to pass through. (Da (Dalton) = a unit used to express molecular mass.)

(In other words, PN or PDRN can have an effect when it’s injected directly into the dermis, but simply applying it on the skin is a completely different story because the stratum corneum gets in the way. For reference, even some of the smallest PDRN molecules are around 100 times larger than 500 Da, and larger ones can be more than 3,000 times larger.)

So skincare companies will say things like:

“But ours is cut into really tiny pieces.”
“They’re smaller fragments.”
“It’s low-molecular-weight PDRN.”

And sure, that sounds convincing.

But even so-called low-molecular-weight PDRN is still tens to hundreds of times larger than what would normally be expected to pass through the skin barrier. So basically, it’s like trying to get a moving truck through a doggy door.

Why a PDRN product can still feel good, and what PDRN ointments are for 04:48–10:24

“But I used a PDRN product and my skin actually felt much better?”

That may be true, but chances are PDRN wasn’t the only thing in the product.

You were probably using other products as well, and the formula itself may have contained vitamins, moisturizers, or other beneficial ingredients. So the improvement you noticed could very well have come from those ingredients rather than the PDRN itself.

We’ve already had plenty of well-studied ingredients for decades that can help send “repair” signals to the skin in ways similar to what PDRN is supposed to do.

I’ve been making YouTube videos since 2023, and one thing I’ve been talking about from the beginning is the CBA routine:

• Vitamin C

• Vitamin B3 (niacinamide)

• Vitamin A (retinoids, such as retinol)

And unlike PN or PDRN, these ingredients are actually able to penetrate the skin much more effectively.

Unless PN or PDRN is injected directly into the dermis, the effect is essentially minimal.

“Then what about PDRN ointments?”

Those are different.

PDRN ointments are used as over-the-counter medications for damaged skin.

For example, if you fall and scrape your skin badly enough that it bleeds and the dermis becomes exposed, PDRN can actually reach the damaged tissue and potentially help with recovery.

The same idea applies when the skin barrier is already compromised, such as in conditions like atopic dermatitis, seborrheic dermatitis, or rosacea. When the barrier is damaged, PDRN can penetrate more easily and may help support the healing process.

So the key point is:

On healthy, intact skin, you can keep applying PDRN all you want, but it’s unlikely to do much.

The doctor’s personal take

Treatments like Rejuran and so-called “salmon injections” became incredibly popular, so I imagine skincare companies started thinking, “What if we could turn this into a topical skincare product?” And that’s probably how we ended up with so many PDRN creams and serums.

A lot of companies have been researching different ways to improve delivery through the skin.

Some use things like liposomes — basically tiny delivery capsules designed to help ingredients penetrate the skin — while others market PDRN together with MTS / microneedling, which intentionally creates tiny channels in the stratum corneum using very small needles.

There are different approaches, but personally, I still don’t think we’re quite at the point where topical PDRN can reliably get through an intact skin barrier and be fully delivered where it needs to go.

If we eventually find a way to get PDRN all the way into the dermis through topical application, that would honestly be great.

But again, there are already ingredients we know the skin can absorb much more easily, with decades of research behind them.

That includes the CBA routine — Vitamin C, niacinamide (Vitamin B3), and Vitamin A/retinoids — as well as ingredients like adenosine, Matrixyl, and other peptides.

Many of these ingredients have more than 20 years of research and data behind them.

So when we already have so many effective, well-studied ingredients available, I personally don’t see much reason to spend extra money on an expensive PDRN cream or serum.

If you do want to see some benefit from PDRN, it may make more sense when the skin barrier is already compromised — for example, when the skin is injured, irritated, or visibly red.

In other words, not when your skin is healthy and intact.

Final takeaway

PDRN itself is a very interesting and potentially useful ingredient.

But honestly, the problem is simple:

PDRN is too large to get through an intact skin barrier.

So if you actually want PDRN to reach the dermis and have the kind of effect people associate with it, for now, that still means delivering it through an injection rather than simply applying it as a cream or serum.

Good alternatives to PDRN: peptides, Matrixyl, adenosine, niacinamide, Vitamin C, Vitamin B3 (niacinamide), Vitamin A (retinoids, such as retinol) (well-studied ingredients.)

The important thing is to use only the ingredients your skin actually needs.

Just because an ingredient is good doesn’t mean you need to layer a ton of different products.

Don’t get carried away by marketing.

I’d recommend being selective, figuring out what your skin actually needs, and building your routine around only those ingredients.

My own skin story (translator’s note)

Personally, I had really good skin until I was around 20. But after moving to Seoul for university, I started struggling with my skin for reasons I still don’t fully understand. I suddenly developed acne and other issues I had never even dealt with as a teenager.

I struggled with it for about four years.

I’ve also tried some of the ingredients mentioned above as good alternatives to PDRN, but niacinamide in particular never seemed to agree with my skin. Whenever I applied it, my skin would sometimes sting or feel hot, and by the next day it would feel unusually sensitive — almost like something was about to break out. Sometimes I actually did get small pimples.

Thankfully, my skin is doing much better now. I’d say it has improved by around 90%.

For the most part, I just consistently used very gentle toner and moisturizer, while also trying to get enough sleep, being more mindful about what I ate, and using medication prescribed by a dermatologist when needed. Every now and then, I also mixed some of the ingredients mentioned earlier into my moisturizer.

Honestly, though, I still don’t know which of those things made the biggest difference. It was probably a combination of several things.

And I’m guessing everyone here has their own things that work — or don’t work — for their skin.

I think a lot of Koreans, myself included, get a huge amount of skincare information from YouTube.

We watch videos comparing different products, videos from dermatologists, and sometimes even GRWMs or vlogs where people casually talk about what they actually use.

So if you’re curious, it might be worth searching for skincare topics in Korean on YouTube once in a while too.

(Although the quality of YouTube’s automatic translations can be pretty terrible…)

For now, I feel like YouTube and Reddit are probably some of the better options we have for finding detailed personal experiences — things like people documenting how they improved problematic skin, or giving honest updates after using something for a long time.

Personally, I’d love to have a space where people could share those kinds of real experiences, ask questions in real time, and actually talk to each other about what worked and what didn’t.

Reddit is already pretty good for that, but sometimes you do see people quietly mentioning products as part of marketing, and I also wish it were easier to freely share photos and videos when they’re actually useful.

Honestly, I think disguised advertising is worse than advertising itself.

There’s nothing inherently wrong with a YouTuber getting paid to introduce a product they already genuinely used and liked, or tried and ended up liking.

The problem is when advertising is made to look like an ordinary personal recommendation.

Anyway, if I come across more Korean content that I think would be interesting or useful to share, I’ll come back with another translation.

And for the next post, if there’s a topic you’re curious about, or if you’ve dealt with a skin problem yourself and found something that helped — whether that was a product or just a lifestyle change — feel free to share it in the comments.

I think hearing about each other’s real experiences could be helpful to a lot of people here.

Thanks for reading