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Common Clouds Cloud Milk Soothing Redness-Relief Serum Versus Paula's Choice 10% Azelaic Acid Booster

Common Clouds Cloud Milk Soothing Redness-Relief Serum Versus Paula's Choice 10% Azelaic Acid Booster This calming serum is formulated around Azelaic Acid and Centella Asiatica Leaf Extract to calm redness and clear breakouts. This calming treatment is formula

Common Clouds Cloud Milk Soothing Redness-Relief Serum Versus Paula's Choice 10% Azelaic Acid Booster

This calming serum is formulated around Azelaic Acid and Centella Asiatica Leaf Extract to calm redness and clear breakouts.

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

Azelaic Acid

Propanediol

Pentylene Glycol

Glycerin

Centella Asiatica Leaf Extract

Sodium Hyaluronate

Xanthan Gum

Polyacrylate Crosspolymer-6

T-Butyl Alcohol

Phenoxyethanol

Ethylhexylglycerin

Sodium Hydroxide

Citric Acid

Water, Azelaic Acid, Propanediol, Pentylene Glycol, Glycerin, Centella Asiatica Leaf Extract, Sodium Hyaluronate, Xanthan Gum, Polyacrylate Crosspolymer-6, T-Butyl Alcohol, Phenoxyethanol, Ethylhexylglycerin, Sodium Hydroxide, Citric 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

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.

Azelaic acid is a multitasker ingredient that helps treat acne, pigmentation, and irritation. It is a great option for sensitive skin.

What makes it special?

OTC Azelaic acid is usually available in concentrations from 10-15% and anything over requires a prescription.

Here's what each tier does best:

Unlike other acids, azelaic acid will not make your skin more photosensitive/sun sensitive.

Though this ingredient is naturally occurring in grains like wheat, rye, and barley, it is usually synthetically created for cosmetics to ensure stability and effectiveness.

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.

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.

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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. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  7. 07Topically, glycerin does several things at once:
  8. 08Your 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.
  9. 09Aquaporin-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.
  10. 10This 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.
  11. 11Just know very high concentrations (>40%) can feel tacky in low humidity.
  12. 12Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  13. 13Glyceryl 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.
  14. 14Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.
  15. 15This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.
  16. 16A 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.
  17. 17Since 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.
  18. 18Fun fact: The human body also creates Glyceryl Stearate naturally.
  19. 19Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  20. 20It 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.
Source · skinsort.com
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