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PCA Skin Pigment Gel Versus Differin Dark Spot Correcting Serum 2% Hydroquinone

PCA Skin Pigment Gel Versus Differin Dark Spot Correcting Serum 2% Hydroquinone This brightening serum is formulated around Lactic Acid and Kojic Acid to fade the look of dark spots and brighten dull-looking skin. This brightening serum is formulated around Hy

By Peptide Skincare & Beauty Editorial TeamPublished

PCA Skin Pigment Gel Versus Differin Dark Spot Correcting Serum 2% Hydroquinone

This brightening serum is formulated around Lactic Acid and Kojic Acid to fade the look of dark spots and brighten dull-looking skin.

This brightening serum is formulated around Hydroquinone to fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Alcohol Denat.

Hamamelis Virginiana Water

Lactic Acid

Butylene Glycol

Kojic Acid

Azelaic Acid

Alcohol

Hydroxyethylcellulose

Phenylethyl Resorcinol

BHT

Glutathione

Silybum Marianum Fruit Extract

Water, Alcohol Denat., Hamamelis Virginiana Water, Lactic Acid, Butylene Glycol, Kojic Acid, Azelaic Acid, Alcohol, Hydroxyethylcellulose, Phenylethyl Resorcinol, BHT, Glutathione, Silybum Marianum Fruit Extract

Hydroquinone 2%

1,2-Hexanediol

Caprylyl Glycol

Citric Acid

Disodium EDTA

Parfum

Hippophae Rhamnoides Oil

PEG-40 Hydrogenated Castor Oil

Polysorbate 20

Sodium Metabisulfite

Sodium Sulfite

Hydroquinone 2%, 1,2-Hexanediol, Alcohol Denat., Caprylyl Glycol, Citric Acid, Disodium EDTA, Parfum, Hippophae Rhamnoides Oil, Hydroxyethylcellulose, PEG-40 Hydrogenated Castor Oil, Polysorbate 20, Sodium Metabisulfite, Sodium Sulfite, Water

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Alcohol Denat. is an alcohol with a denaturant property. It is created by mixing ethanol with other additives.

The "denat" part just means "denatured"; common denaturants include Denatonium Benzoate, t-butyl alcohol, and Diethyl Phthalate. This step makes the alcohol undrinkable (and lets brand skip taxes related to beverage alcohol).

This ingredient gets a bad rep because it is irritating and drying due to its astringent property. Astringents draw out natural oils in tissue to constrict pores and dry out your skin.

However, alcohol denat. is not all that bad.

Due to its low molecular weight, alcohol denat. tends to evaporate quickly. One study on pig skin found half of applied alcohol evaporated in 10 seconds and less than 3% stayed on skin.

This also helps other ingredients become better absorbed upon application.

Studies are conflicted about whether this ingredient causes skin dehydration. One study from 2005 found adding emollients to propanol-based sanitizer decreased skin dryness and irritation. Another study found irritation only occurs if your skin is already damaged.

Small amounts of alcohol are generally tolerated by oily skin or people who live in humid environments.

The rule of thumb is this ingredient will probably not affect your skin much if it is near the end of an ingredients list.

One thing to note: People with ALDH2 (aldehyde dehydrogenase 2) deficiency may experience skin irritation from continued alcohol use. About 8% of the world's population have this deficiency.

The Cosmetic Ingredient Review Expert Panel has determined denatured alcohols to be safe for use in concentrations between 0.05% and 12% (depending on which denaturant is used).

Also...

This ingredient has antimicrobial and solvent properties.

The antimicrobial property helps preserve products and increase their shelf life. As a solvent, it helps dissolve other ingredients.

Look for formulas that contain glycerin, hyaluronic acid, or panthenol if you want to offset any drying effect.

This ingredient will trip away your skin's natural oils/lipids that help it lock in moisture. This can worsen dryness, trigger eczema flare-ups, and aggravate rosacea.

Be sure to patch test any product with this ingredient if you have dry or sensitive skin, eczema, or rosacea.

Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.

This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.

This ingredient can also be found in pill medicines to help our bodies digest other ingredients.

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. 03Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  4. 04Topically, glycerin does several things at once:
  5. 05Your 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.
  6. 06Aquaporin-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.
  7. 07This 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.
  8. 08Just know very high concentrations (>40%) can feel tacky in low humidity.
  9. 09Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  10. 10Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  11. 11It 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.
  12. 12On 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.
  13. 13Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  14. 14You'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.
  15. 15Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  16. 16Safety-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.
  17. 17Adverse 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.
  18. 18Water. 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.
  19. 19So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
  20. 20You'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!
Source · skinsort.com ⟶
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Product index

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Comparison edit

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