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The INKEY List Beta Hydroxy Acid (BHA) Serum Versus Paula's Choice BHA 9 Treatment

The INKEY List Beta Hydroxy Acid (BHA) Serum Versus Paula's Choice BHA 9 Treatment This acne serum is formulated around Salicylic Acid and Zinc PCA to clear breakouts and refine the look of pores. This acne treatment is formulated around Salicylic Acid to clea

By Peptide Skincare & Beauty Editorial TeamPublished

The INKEY List Beta Hydroxy Acid (BHA) Serum Versus Paula's Choice BHA 9 Treatment

This acne serum is formulated around Salicylic Acid and Zinc PCA to clear breakouts and refine the look of pores.

This acne treatment is formulated around Salicylic Acid to clear breakouts and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Propanediol

Betaine

Salicylic Acid

Sodium Hyaluronate

Zinc PCA

Phenoxyethanol

Hydroxyethylcellulose

Maltodextrin

Sodium Hydroxide

Ethylhexylglycerin

Biosaccharide Gum-1

Trisodium Ethylenediamine Disuccinate

Water, Propanediol, Betaine, Salicylic Acid, Sodium Hyaluronate, Zinc PCA, Phenoxyethanol, Hydroxyethylcellulose, Maltodextrin, Sodium Hydroxide, Ethylhexylglycerin, Biosaccharide Gum-1, Trisodium Ethylenediamine Disuccinate

Propylene Glycol

PEG-75 Stearate

PEG-8

Glycerin

Avena Sativa Kernel Extract

Butylene Glycol

Boerhavia Diffusa Root Extract

Sea Whip Extract

Arginine

Polysorbate 20

Disodium EDTA

Propylene Glycol, PEG-75 Stearate, PEG-8, Water, Salicylic Acid, Glycerin, Avena Sativa Kernel Extract, Butylene Glycol, Boerhavia Diffusa Root Extract, Sea Whip Extract, Arginine, Polysorbate 20, Disodium EDTA

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Salicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, and reduce inflammation.

Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.

Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.

Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.

It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.

While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.

If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

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The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

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Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.
  6. 06Caffeine is a naturally occurring plant compound found in coffee beans, tea leaves, cocoa pods, and guarana.
  7. 07As an antioxidant, caffeine protects your skin from free radical damage caused by UV exposure and envionrmnetal stressors.
  8. 08Early research also shows that caffeine can help calm redness, soothe irritated skin, and support hair growth by stimulating microcirculation in the scalp.
  9. 09You might have seen eye creams marketing caffeine as a depuffing ingredient. This is because it is a vasoconstrictor meaning it can temporarily constrict blood vessels, though clinical evidence for this specific use is still limited.
  10. 10Most skincare products contain this ingredient at concentrations between 1-6%. It is able to penetrate skin easily regardless of skin type or thickness.
  11. 11Just so you know, a very small number of case reports describe caffeine-induced allergy. This ingredient is generally well-tolerated, non-irritating, and non-sensitizing for the majority of people.
  12. 12Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.
  13. 13Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  14. 14It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  15. 15Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  16. 16A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.
  17. 17Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  18. 18Topically, glycerin does several things at once:
  19. 19Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.
  20. 20Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.
Source · skinsort.com ⟶
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