Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Kiehl's Truly Targeted Acne-Clearing Solution Versus Paula's Choice 10% Azelaic Acid Booster

Kiehl's Truly Targeted Acne-Clearing Solution Versus Paula's Choice 10% Azelaic Acid Booster This acne treatment is formulated around Salicylic Acid and Gluconolactone to clear breakouts and refine skin texture. This calming treatment is formulated around Azel

Kiehl's Truly Targeted Acne-Clearing Solution Versus Paula's Choice 10% Azelaic Acid Booster

This acne treatment is formulated around Salicylic Acid and Gluconolactone to clear breakouts and refine skin texture.

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

Salicylic Acid 2%

Water

Gluconolactone

Niacinamide

Butylene Glycol

Glycolic Acid

Sodium Hydroxide

Glycerin

Methyl Gluceth-20

Hydroxyethylcellulose

Caprylyl Glycol

Dipotassium Glycyrrhizate

Salicylic Acid 2%, Water, Gluconolactone, Niacinamide, Butylene Glycol, Glycolic Acid, Sodium Hydroxide, Glycerin, Methyl Gluceth-20, Hydroxyethylcellulose, Caprylyl Glycol, Dipotassium Glycyrrhizate

Azelaic Acid

C12-15 Alkyl Benzoate

Caprylic/Capric Triglyceride

Methyl Glucose Sesquistearate

Cetearyl Alcohol

Glyceryl Stearate

Dimethicone

Salicylic Acid

Adenosine

Glycyrrhiza Glabra Root Extract

Boerhavia Diffusa Root Extract

Allantoin

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.

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.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your 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.

Aquaporin-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.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

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!

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 Side-by-side

  1. 01Water
  2. 02Glycolic Acid
  3. 03Sodium Hydroxide
  4. 04Chamomilla Recutita Flower Extract
  5. 05Aloe Ferox Leaf Juice Extract
  6. 06Camellia Oleifera Leaf Extract
  7. 07Sodium Hyaluronate
  8. 08Panthenol
  9. 09Sodium PCA
  10. 10Propylene Glycol
  11. 11Butylene Glycol
  12. 12Hydroxyethylcellulose
  13. 13Polyquaternium-10
  14. 14Phenoxyethanol
  15. 15Sodium Benzoate
  16. 16Water, Glycolic Acid, Sodium Hydroxide, Chamomilla Recutita Flower Extract, Aloe Ferox Leaf Juice Extract, Camellia Oleifera Leaf Extract, Sodium Hyaluronate, Panthenol, Sodium PCA, Propylene Glycol, Butylene Glycol, Hydroxyethylcellulose, Polyquate…
  17. 17Mandelic Acid
  18. 18Polyacrylate Crosspolymer-6
  19. 19Aloe Barbadensis Leaf Juice
  20. 20Glycerin
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side