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Apostrophe Azelaic Acid 15% Prescription Versus Paula's Choice 10% Azelaic Acid Booster

Apostrophe Azelaic Acid 15% Prescription Versus Paula's Choice 10% Azelaic Acid Booster 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

Apostrophe Azelaic Acid 15% Prescription Versus Paula's Choice 10% Azelaic Acid Booster

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

Azelaic Acid 15%

Aloe Barbadensis Leaf Juice

C13-14 Isoparaffin

Caprylic/Capric Triglyceride

Water

Laureth-7

Phenoxyethanol

Polyacrylamide

Tocopheryl Acetate

Triethylene Glycol

Azelaic Acid 15%, Aloe Barbadensis Leaf Juice, C13-14 Isoparaffin, Caprylic/Capric Triglyceride, Water, Laureth-7, Phenoxyethanol, Polyacrylamide, Tocopheryl Acetate, Triethylene Glycol

Azelaic Acid

C12-15 Alkyl Benzoate

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

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

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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.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

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.

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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. 03Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.
  4. 04The way it works is fairly well mapped out:
  5. 05Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down o…
  6. 06The clinical backing is pretty solid too.
  7. 07A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at…
  8. 08A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.
  9. 09On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.
  10. 10This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.
  11. 11Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.
  12. 12Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  13. 13Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  14. 14Though 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.
  15. 15Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  16. 16Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  17. 17Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  18. 18Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  19. 19Topically, glycerin does several things at once:
  20. 20Your 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.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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