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Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Paula's Choice 10% Azelaic Acid Booster

Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Paula's Choice 10% Azelaic Acid Booster This smoothing exfoliator is formulated around Salicylic Acid and Allantoin to refine skin texture and calm redness. This calming treatment is formulated around

Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Paula's Choice 10% Azelaic Acid Booster

This smoothing exfoliator is formulated around Salicylic Acid and Allantoin to refine skin texture and calm redness.

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

Methylpropanediol

Dicaprylyl Carbonate

C15-19 Alkane

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Salicylic Acid

Propanediol

Inulin

Caprylyl Glycol

Allantoin

Tocopherol

Sodium Hydroxide

Ethylhexylglycerin

Hexylene Glycol

Sorbitan Isostearate

Alpha-Glucan Oligosaccharide

Glycerin

Laminaria Digitata Extract

Albatrellus Confluens Extract

Glycine Soja Oil

Opuntia Ficus-Indica Stem Extract

Galactoarabinan

Citric Acid

Schizophyllan

Maltodextrin

Phenoxyethanol

Water, Methylpropanediol, Dicaprylyl Carbonate, C15-19 Alkane, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Salicylic Acid, Propanediol, Inulin, Caprylyl Glycol, Allantoin, Tocopherol, Sodium Hydroxide, Ethylhexylglycerin, Hexylene Glycol, Sorbitan Isostearate, Alpha-Glucan Oligosaccharide, Glycerin, Laminaria Digitata Extract, Albatrellus Confluens Extract, Glycine Soja Oil, Opuntia Ficus-Indica Stem Extract, Galactoarabinan, Citric Acid, Schizophyllan, Maltodextrin, Phenoxyethanol

Azelaic Acid

C12-15 Alkyl Benzoate

Caprylic/Capric Triglyceride

Methyl Glucose Sesquistearate

Cetearyl Alcohol

Glyceryl Stearate

Dimethicone

Adenosine

Glycyrrhiza Glabra Root Extract

Boerhavia Diffusa Root Extract

Bisabolol

Cyclopentasiloxane

Xanthan Gum

Sclerotium Gum

Butylene Glycol

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.

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.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

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. 02Cetearyl Ethylhexanoate
  3. 03Butylene Glycol
  4. 04Glycereth-26
  5. 05Oenothera Biennis Oil
  6. 06Cetyl Alcohol
  7. 07Neopentyl Glycol Diheptanoate
  8. 08Cyclopentasiloxane
  9. 09Stearic Acid
  10. 10Glyceryl Stearate
  11. 11PEG-100 Stearate
  12. 12Glycerin
  13. 13Cyclohexasiloxane
  14. 14Dimethicone
  15. 15Panthenol
  16. 16Palmitoyl Tripeptide-1
  17. 17Palmitoyl Tetrapeptide-7
  18. 18Sodium Hyaluronate
  19. 19Tocopheryl Linoleate
  20. 20Tocopheryl Acetate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side