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The INKEY List Glycolic Acid Exfoliating Scalp Scrub Versus The INKEY List Salicylic Acid Exfoliating Scalp Treatment

The INKEY List Glycolic Acid Exfoliating Scalp Scrub Versus The INKEY List Salicylic Acid Exfoliating Scalp Treatment What's inside Key Ingredients Benefits Concerns Ingredients Side-by-side Water Glycolic Acid Propanediol Hydrogenated Castor Oil PEG-40 Hydrog

The INKEY List Glycolic Acid Exfoliating Scalp Scrub Versus The INKEY List Salicylic Acid Exfoliating Scalp Treatment

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycolic Acid

Propanediol

Hydrogenated Castor Oil

PEG-40 Hydrogenated Castor Oil

Betaine

Glycerin

Sodium Hydroxide

Polyquaternium-10

Phenoxyethanol

Benzyl Alcohol

Alpha-Glucan Oligosaccharide

Citronellyl Methylcrotonate

Panthenol

Ethylhexylglycerin

Dehydroacetic Acid

Mannitol

Trisodium Ethylenediamine Disuccinate

Sodium Benzoate

Tetraselmis Suecica Extract

Lactic Acid

Potassium Benzoate

Water, Glycolic Acid, Propanediol, Hydrogenated Castor Oil, PEG-40 Hydrogenated Castor Oil, Betaine, Glycerin, Sodium Hydroxide, Polyquaternium-10, Phenoxyethanol, Benzyl Alcohol, Alpha-Glucan Oligosaccharide, Citronellyl Methylcrotonate, Panthenol, Ethylhexylglycerin, Dehydroacetic Acid, Mannitol, Trisodium Ethylenediamine Disuccinate, Sodium Benzoate, Tetraselmis Suecica Extract, Lactic Acid, Potassium Benzoate

Salicylic Acid

Polyquaternium-37

Hexylene Glycol

Capryloyl Glycine

Xylitylglucoside

Water, Propanediol, Salicylic Acid, Betaine, Panthenol, PEG-40 Hydrogenated Castor Oil, Phenoxyethanol, Polyquaternium-37, Hexylene Glycol, Capryloyl Glycine, Citronellyl Methylcrotonate, Sodium Hydroxide, Ethylhexylglycerin, Xylitylglucoside, Trisodium Ethylenediamine Disuccinate

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.

Betaine is a humectant. Like hyaluronic acid, it helps attract and retain moisture in the skin. It’s known for being gentle and for helping the skin maintain balanced hydration.

Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte.

Some studies suggest betaine may support making skin tone more even.

Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability.

Betaine is also known as trimethylglycine.

Citronellyl Methylcrotonate is a fragrance.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

PEG-40 Hydrogenated Castor Oil is an emulsifier derived from castor oil.

As an emulsifying agent, it helps other ingredients like fragrances and fat-soluble vitamins dissolve cohesively.

Due to its large molecule size, it doesn't penetrate beyond the skin's surface.

This ingredient has a solid regulatory track record; the CIR Expert Panel first concluded it was safe for use in cosmetics at concentrations up to 100% in 1997. A 2012 reassessment reaffirmed that finding. Safety studies have also found no irritation or evidence of toxicity.

A 2019 study did find this ingredient to grow Malassezia, so this ingredient may not be fungal acne safe.

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.

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.

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.

Trisodium Ethylenediamine Disuccinate is used to help stabilize a product.

It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.

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. 03Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  4. 04Like 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.
  5. 05However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  6. 06Due 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.
  7. 07In skincare formulas, citric acid can:
  8. 08While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  9. 09Most 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.
  10. 10Rosacea 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.
  11. 11However, 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…
  12. 12Coconut acid is a mixture of fatty acids obtains by hydrolyzing coconut oil and then distilling the fatty acid portion. It works as a cleansing surfactant, emollient, and emulsifier depending on the formulation.
  13. 13This ingredient is not a single compound but reflects the fatty acid profile of coconut oil itself, which is about 90% saturated.
  14. 14The dominant fatty acid is lauric acid (44-54%) and then myristic acid (13-19%). There are also small amounts of caprylic, capric, palmitic, oleic, and linoleic acids.
  15. 15Human testing from CIR has shown no indication this ingredient to be a primary irritant, sensitizer, or phototoxic compound. It's COSMOS-approved for natural and organic products.
  16. 16Due to the fatty acid content, this ingredient may not be fungal acne safe. Research has confirmed Malassezia can use lauric acid as a food source.
  17. 17Peg-120 Methyl Glucose Dioleate is used to improve texture and stability of a product. It is sugar based and helps thicken a product.
  18. 18Once applied, it also creates a thin film to trap moisture in. This helps keep your skin hydrated.
  19. 19This ingredient is the polyethylene glycol ether of the diester of oleic acid and methylglucose. The 120 represents an average of 120 moles of ethylene oxide.
  20. 20There is limited research on this ingredient, although it is considered safe to use in skincare products.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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