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Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant Versus Perrigo Tretinoin Cream, USP 0.025%

Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant Versus Perrigo Tretinoin Cream, USP 0.025% This smoothing exfoliator is formulated around Salicylic Acid to refine skin texture and refine the look of pores. What's inside Key Ingredients Benefits Concerns

By Peptide Skincare & Beauty Editorial TeamPublished

Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant Versus Perrigo Tretinoin Cream, USP 0.025%

This smoothing exfoliator is formulated around Salicylic Acid to refine skin texture and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Methylpropanediol

Butylene Glycol

Salicylic Acid

Polysorbate 20

Camellia Oleifera Leaf

Sodium Hydroxide

Tetrasodium EDTA

Water, Methylpropanediol, Butylene Glycol, Salicylic Acid, Polysorbate 20, Camellia Oleifera Leaf, Sodium Hydroxide, Tetrasodium EDTA

Tretinoin

Stearic Acid

Isopropyl Myristate

PEG-40 Stearate

Stearyl Alcohol

Xanthan Gum

Sorbic Acid

BHT

Tretinoin, Stearic Acid, Isopropyl Myristate, PEG-40 Stearate, Stearyl Alcohol, Xanthan Gum, Sorbic Acid, BHT, Water

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.

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.

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. 03Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  4. 04Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.
  5. 05It plays several roles in a formula:
  6. 06Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.
  7. 07Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  8. 08However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  9. 09Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.
  10. 10Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.
  11. 11Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.
  12. 12This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.
  13. 13A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.
  14. 14Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  15. 15Topically, glycerin does several things at once:
  16. 16Your 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.
  17. 17Aquaporin-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.
  18. 18This 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.
  19. 19Just know very high concentrations (>40%) can feel tacky in low humidity.
  20. 20Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Source · skinsort.com ⟶
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