COSRX BHA Blackhead Power Liquid Review: Paula’s BHA Sucks Balls

by | Last updated Apr 18, 2020 | Reviews | 104 comments

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It’s finally time to discuss my third holy grail: the COSRX BHA Blackhead Power Liquid. 🙂

cosrx bha blackhead power liquid

See price on Amazon

I don’t think there’s been one product that has more single-handedly given me that sexy “glow” and gotten rid of my closed comedones like this bad puppy has.

As you may remember, I’m not a big fan of the Paula’s Choice 2% BHA Liquid (Extra Strength), so this review will be a comparison of sorts including some before and after picutres of my forehead to illustrate the difference the COSRX BHA made!

Let’s waste no time and get right into it.

Ingredients and Benefits.

Like most COSRX products, this one lured me in with its nice simple ingredient list. Check it out.

cosrx bha blackhead power liquid ingredients

Salix alba (willow) bark water, butylene glycol, betaine salicylate, niacinamide, 1,2-hexanediol, arginine, panthenol, sodium hyaluronate, xanthan gum, ethyl hexanediol.

Great, isn’t it? On a firsthand glance we already see that they’ve completely cut out all the unnecessary ingredients that are little more than filler.

  • Willow Bark Water

People often confuse willow bark extract with salicylic acid. They are not the same thing. Willow bark simply has salicin in it, which in the presence of enzymes, or when absorbed orally, converts into salicylic acid.

So no, this won’t turn into an ungodly amount of salicylic acid when applied on skin. Rather, it’s put into this formula because of the soothing and anti-inflammatory benefits it has. Something I think COSRX deserves credit for!

They always try to really maximize their formulas, so rather than simply filling it up with water they went that little extra mile to sneak in some added benefits. 🙂

  • Betaine Salicylate

This is essentially the “salicylic acid” in the formula. Just a very quick refresher on what salicylic acid is in case you don’t know. It’s a chemical exfoliant that’s known for its keratolytic, comedolytic, bacteriostatic, and anti-inflammatory properties.

If all that sounds confusing, here’s the english translation: it sloughs off dead skin cells, unclogs pores, reduces inflammation, and creates a hostile environment for the bacteria that exacerbates acne. So overall, salicylic acid is pretty great!

With that said, I think the biggest thing everyone wondering about the COSRX BHA is whether its variation of salicylic acid (betaine salicylate) is as effective as salicylic acid itself. It’s a hard question to answer because of limited research, but I’ll try my best using the given information available and share some personal experience as well.

What do we know about Betaine Salicylate?

It’s derived from sugar beets, and many consider it a more gentle alternative to salicylic acid because it isn’t pH dependent, meaning it does not require an acidic environment to work optimally.

Fun fact: salicylic acid has to be formulated with a pH of 3-4 to work best, otherwise it might precipitate out of the solution and form crystals like this!

salicylic acid crystallization

I’ve gotten several questions about the controversy over the COSRX BHA having a higher pH than advertised (around 5.5). Rest assured, this is not something we have to worry about with neutralized forms of salicylic acid (i.e. salicylate).

In fact, there is some evidence that salicylate (the active BHA in COSRX) at pH 6.5, works just as well as salicylic acid in an acidic vehicle (pH 3.12) after only two days of application.

Moreover, one study that found 4% betaine salicylate was just as effective as 2% salicylic acid after 10 days, without the drying or irritating effects that salicylic acid had.

You can essentially think of betaine salicylate as a more gentle and moisturizing salicylic acid. Or as the researchers put it themselves,

“This new product becomes ideal for leave-on and rinse off compositions that require mild exfoliation and antimicrobial properties blended with substantial moisturizing and anti-irritation claims.” (1)

Do note however, that the sample size of this study was very small, so it’s not the most reliable piece of information. But based off of PERSONAL EXPERIENCE alone, I think betaine salicylate has potential to treat acne (specifically clogged pores and blackheads) better than salicylic acid itself. Here’s why:

When trying to prevent and treat breakouts is very important that we limit irritation whenever possible. That’s something I discuss in my how to treat acne article. Irritated skin is less resilient and capable of fighting off pathogens and infections, which could further irritate breakouts. It doesn’t help that salicylic acid is often irritating on the skin.

Personally, I was never able to use the Paula’s Choice 2% BHA because it was simply too drying. I would try to introduce it into my skincare routine time and time again, only to my disappointment and newly found irritated skin.

This would in turn lead to more clogged pores, and it just became a never-ending cycle of trying to use more product to treat the problems that the product was causing!

UPDATE 7/12/17:  The Paula’s Choice BHA also broke me out because it contains polysorbate-20, which aggravates the fungal skin sensitivities I have. If you want to read more about how to treat “fungal acne,” or adult acne that is incredibly stubborn, check out this guide on malassezia I wrote that took me 3 months to finish!

Now back to our scheduled programming….

After doing some research I decided to switch to the COSRX BHA because everyone and their mom was raving about it and how gentle it was. Here’s the difference it made in about 45 days.

ruptured moisture barrier

The photo on the left was what the Paula’s Choice Extra Strength BHA did to my forehead after trying to use it 4 times weekly for about a month. In other words, it completely nuke my moisture barrier and acid mantle (and aggravated my malassezia / fungal sensitivities)! Just looking at the photo makes me cringe. If you didn’t know what over-exfoliated skin looks like…. well, now you do.

And I have reason to believe that this excessive irritation didn’t just happen because the skin on my face is sensitive. Why do I say that? Because my hands are pretty tough. I usually wash them anywhere from 5-10 times per day. Yes, I know that’s bad! Don’t remind me.

Yet they were hardly ever dry until I introduced the Paula’s Choice BHA! Every stinking time I tried using it I would have flakey dry skin on the palm of my hands after a few days.

NOTE: I pour the BHA into my palms to save product. I haven’t used cotton balls in ages.

So you can see the complete 360 the COSRX BHA made my skin do! It doesn’t feel nearly as dry anymore (winter is approaching so I’m still currently experiencing some dryness), and I can get away with using it every other day without experiencing any irritation whatsoever. At one point I was using it every day for about two weeks, but I ended up getting some minor flakey skin so reduced the frequency.

To add to that, every morning I wake up I feel like it gives my skin a bit of a glow! I’ve NEVER experienced this with a product before, so to say I’m beyond the moon about it is an understatement.

And best of all it’s gotten rid of some stubborn closed comedones that I had for months! I was literally beginning to think that they were just going to be a permanent part of my face. Several 15% salicylic acid peels hardly made them budge. But I sh*t you not, within a few days of using the COSRX BHA one of them nearly shot out of my face!

And a lot of the other closed comedones I had have since disappeared as well. Cooler yet, it didn’t even make my skin purge. Generally when I use active ingredients they will make the clogs I have come to a head, and I’ll be left with a nice little whitehead for a couple of days. -___-

But for the first time ever, the closed comedones seemed to just disappear on their own! In other words, they didn’t come to a head. And this hasn’t just happened to me. I have read several people on the r/asianbeauty subreddit report very similar experiences.

  • Niacinamide

One of my all-time favorite ingredients. This does a little bit of everything. It’s very effective at brightening skin tone, treating hyperpigmentation (skin discoloration), and hydrating the skin. (23) There’s also ample evidence that it has anti-aging benefits. (4567)  In fact, one study showed it’s anti-wrinkle properties are akin to tretinoin! (8)

It also increases collagen production, and does comparatively better than antibiotics in treating acne. (910)

  • Arginine

An amino acid with antioxidant properties.

  • Panthenol

A vitamin that’s part of the B complex. It improves barrier function, hydrates the skin, promotes keratinocyte differentiation, and may help treat burn wounds. (11121314) A study on children also found that it could help treat dermatitis. (15)

  • Sodium Hyaluronate

Also known as hyaluronic acid. This is a very potent humectant that’s capable of holding 1000 times water weight.

It hydrates the skin by slowing down the rate at which water evaporates from its surface by drawing moisture from the dermis (deeper layer of skin) and the atmosphere. Studies have also shown it helps significantly speed up wound healing. (16171819)

Related reading: Hyaluronic Acid for Skin: Literally EVERYTHING You Need to Know!

And that does it for the ingredient list! Just a very basic formula that packs a punch with the things that it does include.

Application, Feel, and Scent.

This thing applies gloriously! I’m going to have to throw shade at the Paula’s choice BHA again (sorry). For comparison sake, just look at the difference in spreadability/finish between the both of them.

(COSRX BHA Blackhead Power Liquid)

See on Amazon


(Paula’s Choice SKIN PERFECTING 2% BHA Liquid)

See on Amazon


For starters, the COSRX BHA has the most gorgeous slip! It feels like silky water and spreads super easily. And look at the beautiful dewy finish it leaves behind!

On the other hand, the Paula’s Choice BHA takes for-freaking-ever to dry, and once it does it leaves you looking like an oily mess (probably the high amount of methylpropanediol). Not only that, it adheres to the surface of skin, and requires more effort to spread, whereas the COSRX BHA just glides smoothly (again, most likely the higher amount of solvents).

Oh, and the Paula’s Choice BHA smells like a** too. I understand that Paula’s Choice has a quarrel against fragrances because they’re potentially irritating, which is good. Kudos to them. But goodness, this stuff stinks haha.

On the other hand the COSRX BHA is reminiscent of my childhood because it smells exactly like those lemon lime green shots the ice cream man use to sell! If you have any idea what I’m talking about you’re awesome. :p

And last but not least, the Paula’s Choice BHA isn’t hydrating in the slightest, whereas the COSRX BHA provides some moisture.

How to Use the COSRX BHA Blackhead Power Liquid.

Because this is a pH dependent product it’s important to use it in the right step of your skincare routine. This will be after cleanser but BEFORE moisturizer. Because many people from the Asian beauty community use it, here’s a sample routine considering MANY things. Of course, not all of this stuff may apply to you so adjust it accordingly.

  • OCM or Oil cleanser.
  • Gentle pH-balanced cleanser.
  • Acid toner
  • Low pH serums (e.g. ascorbic acid vitamin C). Wait 20-30 minutes.
  • Use the COSRX BHA Blackhead Power Liquid here. Wait 20-30 minutes. 
  • AHAs (lactic, glycolic, mandelic etc.). Wait 20-30 minutes.
  • Retinoids like tretinoin.
  • Hydrating toners
  • Essence
  • Serum
  • Ampoule
  • Emulsion
  • Creams, moisturizers, sleeping packs, or sunscreen.
  • Face oil
  • Occlusives like vaseline or aquaphor.


  • Ingredients: 5/5

Has a very minimal formula without any unnecessary ingredients. But the stuff that’s in there packs a punch including 4% betaine salicylate (a gentler form of salicylic acid), niacinamide, arginine, panthenol, sodium hyaluronate, and willow bark water!

  • Benefits: 5/5

Gives the skin a glow, treats discoloration like hyperpigmentation, unclogs pores, prevents breakouts, and provides some hydration.

  • Application: 5/5

Feels like silky water and spreads very easily. Dries leaving a dewy finish, and smells faintly of lemon lime shots! :p

  • Packaging: 5/5

Comes in a beautiful and sturdy bottle with a pump dispenser for easy application.

  • Value: 5/5

Freaking cheap considering how long it will last you and what a great product it is.

Overall: 5/5 — BOOM. Holy grail status unlocked. This is the 2nd Asian beauty product on this blog to do so. The only other being the Benton Snail Bee High Content Essence (see full review).


Check on Amazon

And that does it for this review! I highly recommend the COSRX BHA if you’re on the lookout for a gentle BHA. If you want a stronger and more traditional salicylic acid exfoliant, I don’t think you can go wrong with stridex in a red box (full review here)! It’s the only pure salicylic acid product I’ve tried that worked for my skin because I’m prone to fungal acne / malassezia flare-ups.

Hope you’ve enjoyed this article! :-))



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