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Paula's Choice 10% Azelaic Acid Booster Versus La Roche-Posay EFFACLAR K+

Paula's Choice 10% Azelaic Acid Booster Versus La Roche-Posay EFFACLAR K+ This calming treatment is formulated around Azelaic Acid and Salicylic Acid to calm redness and fade the look of dark spots. This oil-control moisturizer is formulated around Salicylic A

By Peptide Skincare & Beauty Editorial TeamPublished

Paula's Choice 10% Azelaic Acid Booster Versus La Roche-Posay EFFACLAR K+

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

This oil-control moisturizer is formulated around Salicylic Acid and Zinc PCA to balance excess oil and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Propylene Glycol

Octyldodecanol

PEG-100 Stearate

Ammonium Polyacryloyldimethyl Taurate

Zinc PCA

Sarcosine

Sodium Hydroxide

Silica

Silica Silylate

Perlite

Carnosine

Disodium EDTA

Capryloyl Salicylic Acid

Pentylene Glycol

Acrylates Copolymer

Cetyl Alcohol

Tocopherol

Parfum

Water, Propylene Glycol, Octyldodecanol, Dimethicone, PEG-100 Stearate, Glyceryl Stearate, Salicylic Acid, Ammonium Polyacryloyldimethyl Taurate, Zinc PCA, Sarcosine, Sodium Hydroxide, Silica, Silica Silylate, Perlite, Carnosine, Disodium EDTA, Capryloyl Salicylic Acid, Xanthan Gum, Pentylene Glycol, Acrylates Copolymer, Cetyl Alcohol, Butylene Glycol, Tocopherol, Parfum

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.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.

Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.

This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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. 03Avena Sativa Kernel Extract is is derived from colloidal oatmeal. Besides being a healthy breakfast, oats have many benefits in skincare too.
  4. 04This ingredient helps sooth, hydrate, and protect the skin. The starches in colloidal oatmeal are able to bind water, keeping the skin hydrated.
  5. 05The cellulose and fiber in colloidal oatmeal help reduce inflammation. This can also help the skin feel softer.
  6. 06Colloidal Oatmeal is also an antioxidant. Antioxidants protect our skin from free-radical damage.
  7. 07Oatmeal also contains beneficial compounds:
  8. 08This ingredient is created by mixing grounded oatmeal and a liquid base.
  9. 09Benzoic Acid is an organic acid that shows up in cosmetics as a preservative. It helps keep a product from spoiling by holding back the growth of yeast, mold, and some bacteria.
  10. 10This ingredient also functions as a fragrance ingredient that helps mask the unpleasant scent of other ingredients.
  11. 11The way it works is worth understanding; benzoic acid works when the formula is acidic. It is able to sneak into a microbe's cell and mess up how it functions to stop it from growing in an acidic product.
  12. 12However, the acid switches to an inactive form and stops working if a product isn't acidic enough (above ~5 pH). This is why you'll often see it in low pH products or teamed up with other preservatives to cover the gap.
  13. 13Safety wise, it's one of the better studied preservatives out there.
  14. 14The Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe for use in cosmetic formulations at concentrations up to 5%.
  15. 15A large international review found this ingredient had no effects on the human body and had low irritation potential.
  16. 16Just so you know, real world use is usually much lower than the 5% ceiling (usually 1% of less).
  17. 17The EU caps it at 2.5% in rinse-off products, 1.7% in oral care, and 0.5% in leave-on products.
  18. 18One thing worth mentioning (it's nothing to worry about): some people get a little stinging or flushing where they apply it. This isn't a true allergy; it's a temporary and harmless reaction. This is the same kind of mild tingle you might notice fro…
  19. 19Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  20. 20Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
Source · skinsort.com ⟶
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