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Skin science article

La Roche-Posay Effaclar Duo (+) Corrective Unclogging Care Versus Paula's Choice Regular Strength Daily Skin Clearing Treatment with 2.5% Benzoyl Peroxide

La Roche-Posay Effaclar Duo (+) Corrective Unclogging Care Versus Paula's Choice Regular Strength Daily Skin Clearing Treatment with 2.5% Benzoyl Peroxide This acne moisturizer is formulated around Niacinamide and Zinc PCA to clear breakouts and refine the loo

La Roche-Posay Effaclar Duo (+) Corrective Unclogging Care Versus Paula's Choice Regular Strength Daily Skin Clearing Treatment with 2.5% Benzoyl Peroxide

This acne moisturizer is formulated around Niacinamide and Zinc PCA to clear breakouts and refine the look of pores.

This acne treatment is formulated around Benzoyl Peroxide and Bisabolol to clear breakouts and calm redness.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Dimethicone

Isocetyl Stearate

Niacinamide

Isopropyl Lauroyl Sarcosinate

Silica

Ammonium Polyacryloyldimethyl Taurate

Methyl Methacrylate Crosspolymer

Potassium Cetyl Phosphate

Sorbitan Oleate

Zinc PCA

Glyceryl Stearate Se

Isohexadecane

Sodium Hydroxide

Myristyl Myristate

2-Oleamido-1,3-Octadecanediol

Aluminum Starch Octenylsuccinate

Mannose

Poloxamer 338

Disodium EDTA

Capryloyl Salicylic Acid

Caprylyl Glycol

Vitreoscilla Ferment

Xanthan Gum

Polysorbate 80

Acrylamide/Sodium Acryloyldimethyltaurate Copolymer

Salicylic Acid

Piroctone Olamine

Parfum

Water, Glycerin, Dimethicone, Isocetyl Stearate, Niacinamide, Isopropyl Lauroyl Sarcosinate, Silica, Ammonium Polyacryloyldimethyl Taurate, Methyl Methacrylate Crosspolymer, Potassium Cetyl Phosphate, Sorbitan Oleate, Zinc PCA, Glyceryl Stearate Se, Isohexadecane, Sodium Hydroxide, Myristyl Myristate, 2-Oleamido-1,3-Octadecanediol, Aluminum Starch Octenylsuccinate, Mannose, Poloxamer 338, Disodium EDTA, Capryloyl Salicylic Acid, Caprylyl Glycol, Vitreoscilla Ferment, Xanthan Gum, Polysorbate 80, Acrylamide/Sodium Acryloyldimethyltaurate Copolymer, Salicylic Acid, Piroctone Olamine, Parfum

Propylene Glycol

Benzoyl Peroxide

Bisabolol

Allantoin

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Hydroxyethylcellulose

Sodium Citrate

Laureth-4

Hexylene Glycol

Phenoxyethanol

Water, Propylene Glycol, Benzoyl Peroxide, Bisabolol, Allantoin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Hydroxyethylcellulose, Sodium Citrate, Laureth-4, Caprylyl Glycol, Sodium Hydroxide, Disodium EDTA, Hexylene 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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.

This ingredient mainly works behind the scenes and helps with:

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

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.

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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. 03Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin.
  4. 04Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for:
  5. 05Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.
  6. 06One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.
  7. 07While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.
  8. 08The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% be…
  9. 09Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.
  10. 10Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at…
  11. 11Read more about other types of Vitamin C:
  12. 12Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.
  13. 13Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  14. 14Topically, glycerin does several things at once:
  15. 15Your 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.
  16. 16Aquaporin-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.
  17. 17This 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.
  18. 18Just know very high concentrations (>40%) can feel tacky in low humidity.
  19. 19Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  20. 20Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
Source · skinsort.com
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Comparison edit

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