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Skin science article

Farmacy Brighten Up 3% TXA Dark Spot Toner with Azelaic Acid + PHA Versus The INKEY List SuperSolutions 10% Azelaic Serum Redness Relief Solution

Farmacy Brighten Up 3% TXA Dark Spot Toner with Azelaic Acid + PHA Versus The INKEY List SuperSolutions 10% Azelaic Serum Redness Relief Solution This brightening toner is formulated around Gluconolactone and Tranexamic Acid to fade the look of dark spots and

Farmacy Brighten Up 3% TXA Dark Spot Toner with Azelaic Acid + PHA Versus The INKEY List SuperSolutions 10% Azelaic Serum Redness Relief Solution

This brightening toner is formulated around Gluconolactone and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin.

This calming serum is formulated around Azelaic Acid to calm redness and clear breakouts.

What's inside

Key Ingredients

Benefits

Concerns

No concerns

Ingredients Side-by-side

Water

Gluconolactone

Pentylene Glycol

Isopentyldiol

Tranexamic Acid

Betaine

Propanediol

Azelaic Acid

Ascorbic Acid

Citrus Aurantium Amara Fruit Extract

Citrus Aurantium Sinensis Peel Extract

Citrus Reticulata Fruit Extract

Glycerin

Allantoin

Polyglycerin-6

Inulin

Fructose

Glucose

Xanthan Gum

Cellulose Gum

Lactic Acid

Citric Acid

Sodium Phytate

Cellulose

Water, Gluconolactone, Pentylene Glycol, Isopentyldiol, Tranexamic Acid, Betaine, Propanediol, Azelaic Acid, Ascorbic Acid, Citrus Aurantium Amara Fruit Extract, Citrus Aurantium Sinensis Peel Extract, Citrus Reticulata Fruit Extract, Glycerin, Allantoin, Polyglycerin-6, Inulin, Fructose, Glucose, Xanthan Gum, Cellulose Gum, Lactic Acid, Citric Acid, Sodium Phytate, Cellulose

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Phenoxyethanol

Acacia Senegal Gum

Ethylhexylglycerin

Polysorbate 60

Sorbitan Isostearate

Maltodextrin

Sodium Hydroxide

Hydrolyzed Gardenia Florida Extract

Gardenia Florida Fruit Extract

Polylysine

Water, Azelaic Acid, Propanediol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Phenoxyethanol, Acacia Senegal Gum, Xanthan Gum, Allantoin, Glycerin, Ethylhexylglycerin, Polysorbate 60, Sorbitan Isostearate, Maltodextrin, Sodium Hydroxide, Hydrolyzed Gardenia Florida Extract, Gardenia Florida Fruit Extract, Polylysine

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.

Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.

Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

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.

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. 03Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken, emulsify, and improve the texture of products.
  4. 04As an emulsifier, it helps stabilize oil-in-water emulsions to give products an elegant feel when applied.
  5. 05It can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.
  6. 06A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.
  7. 07Also known as Avobenzone, this ingredient is an oil-soluble used to absorb the full spectrum of UVA rays (peak 357 nm).
  8. 08It's one of the most effective UVA filters available but has a major caveat of photostability: avobenzone is susceptible to photodegradation.
  9. 09This means it can lose efficacy when exposed to sunlight without the help of a stabilizing agent.
  10. 10Studies show antioxidants (like vitamin E or vitamin C) and some UV filters (like octocrylene and Tinosorb S) can meaningfully improve its stability in a formulation.
  11. 11The maximum allowable concentration according to regulation is 3% in the US + Canada, and 5% in the EU, Australia, China, Korea, and ASEAN countries.
  12. 12It has a well-support safety profile: a comprehensive 2025 review found minimal toxicity with no evidence of carcinogenicity.
  13. 13Overall, avobenzone is a safe and regulated ingredient used in sunscreen for over 40 years.
  14. 14Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  15. 15Topically, glycerin does several things at once:
  16. 16Your 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.
  17. 17Aquaporin-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.
  18. 18This 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.
  19. 19Just know very high concentrations (>40%) can feel tacky in low humidity.
  20. 20Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Source · skinsort.com
02

Product index

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Comparison edit

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