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Skin science article

Farmacy Brighten Up 3% TXA Dark Spot Toner with Azelaic Acid + PHA Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant

Farmacy Brighten Up 3% TXA Dark Spot Toner with Azelaic Acid + PHA Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant This brightening toner is formulated around Gluconolactone and Tranexamic Acid to fade the look of dark

Farmacy Brighten Up 3% TXA Dark Spot Toner with Azelaic Acid + PHA Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant

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

This smoothing exfoliator is formulated around Mandelic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin.

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

2,3-Butanediol

Mandelic Acid

Sodium Hydroxide

Myrica Cerifera Fruit Extract

Akebia Quinata Stem Extract

Prunus Lannesiana Flower Extract

Lactobacillus Ferment Lysate

Saccharomyces Lysate

Achillea Millefolium Extract

Saccharide Isomerate

Arginine

Hydroxyacetophenone

Butylene Glycol

Sodium Citrate

1,2-Hexanediol

Caprylyl Glycol

Sodium Benzoate

Water, 2,3-Butanediol, Mandelic Acid, Lactic Acid, Sodium Hydroxide, Myrica Cerifera Fruit Extract, Akebia Quinata Stem Extract, Prunus Lannesiana Flower Extract, Lactobacillus Ferment Lysate, Saccharomyces Lysate, Achillea Millefolium Extract, Saccharide Isomerate, Arginine, Hydroxyacetophenone, Butylene Glycol, Sodium Phytate, Pentylene Glycol, Xanthan Gum, Citric Acid, Sodium Citrate, 1,2-Hexanediol, Caprylyl Glycol, Sodium Benzoate

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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.

Its main role is to exfoliate the surface of the skin by loosening the “glue” that holds dead skin cells together. Shedding those old cells leads to smoother, softer, and more even-toned skin.

Because lactic acid molecules are larger than glycolic acid, they don’t penetrate as deeply. This means they’re less likely to sting or irritate, making it a great choice for beginners or those with sensitive skin.

Like glycolic acid, it can:

Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate.

Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome.

To get results, choose products with a pH between 3-4.

Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time.

Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations.

When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH.

Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.

Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshness of stronger acids.

Read more about some other popular AHA's here:

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

Sodium Phytate is the synthetic salt form of phytic acid. Phytic acid is an antioxidant and can be found in plant seeds.

Sodium Phytate is a chelating agent. Chelating agents help prevent metals from binding to water. This helps stabilize the ingredients and the product.

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.

01

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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  6. 06Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.
  7. 07What it does:
  8. 08Dimethicone comes in different viscosities:
  9. 09Depending on the viscosity, dimethicone has different properties.
  10. 10Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
  11. 11This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.
  12. 12Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.
  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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Product index

Related product references

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Comparison edit

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