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COSRX AHA/BHA Clarifying Treatment Toner Versus Paula's Choice 10% Azelaic Acid Booster

COSRX AHA/BHA Clarifying Treatment Toner Versus Paula's Choice 10% Azelaic Acid Booster This smoothing toner is formulated around Salix Alba Bark Water and Glycolic Acid to refine skin texture and refine the look of pores. This calming treatment is formulated

By Peptide Skincare & Beauty Editorial TeamPublished

COSRX AHA/BHA Clarifying Treatment Toner Versus Paula's Choice 10% Azelaic Acid Booster

This smoothing toner is formulated around Salix Alba Bark Water and Glycolic Acid to refine skin texture and refine the look of pores.

This calming treatment is formulated around Azelaic Acid and Salicylic Acid to calm redness and fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Salix Alba Bark Water

Pyrus Malus Fruit Water

Butylene Glycol

1,2-Hexanediol

Sodium Lactate

Glycolic Acid

Betaine Salicylate

Allantoin

Panthenol

Ethyl Hexanediol

Water, Salix Alba Bark Water, Pyrus Malus Fruit Water, Butylene Glycol, 1,2-Hexanediol, Sodium Lactate, Glycolic Acid, Betaine Salicylate, Allantoin, Panthenol, Ethyl Hexanediol

Azelaic Acid

C12-15 Alkyl Benzoate

Caprylic/Capric Triglyceride

Methyl Glucose Sesquistearate

Glycerin

Cetearyl Alcohol

Glyceryl Stearate

Dimethicone

Salicylic Acid

Adenosine

Glycyrrhiza Glabra Root Extract

Boerhavia Diffusa Root Extract

Bisabolol

Cyclopentasiloxane

Xanthan Gum

Sclerotium Gum

Propanediol

Phenoxyethanol

Water, Azelaic Acid, C12-15 Alkyl Benzoate, Caprylic/Capric Triglyceride, Methyl Glucose Sesquistearate, Glycerin, Cetearyl Alcohol, Glyceryl Stearate, Dimethicone, Salicylic Acid, Adenosine, Glycyrrhiza Glabra Root Extract, Boerhavia Diffusa Root Extract, Allantoin, Bisabolol, Cyclopentasiloxane, Xanthan Gum, Sclerotium Gum, Propanediol, Butylene Glycol, Phenoxyethanol

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.

Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.

Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though 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.

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!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

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

01

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. 03Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken, emulsify, and improve the texture of products.
  4. 04As an emulsifier, it helps stabilize oil-in-water emulsions to give products an elegant feel when applied.
  5. 05It can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.
  6. 06A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.
  7. 07Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  8. 08Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
  9. 09However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  10. 10Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
  11. 11In skincare formulas, citric acid can:
  12. 12While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  13. 13Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
  14. 14Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.
  15. 15However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's…
  16. 16Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  17. 17The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure …
  18. 18Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  19. 19Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  20. 20Topically, glycerin does several things at once:
Source · skinsort.com ⟶
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