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Medik8 Liquid Peptides Versus Allies of Skin Peptide & Antioxidants Firming Daily Treatment

Medik8 Liquid Peptides Versus Allies of Skin Peptide & Antioxidants Firming Daily Treatment This anti-aging serum is formulated around Carnosine and Palmitoyl Tripeptide-5 to soften the look of wrinkles and refine skin texture. This anti-aging moisturizer is f

Medik8 Liquid Peptides Versus Allies of Skin Peptide & Antioxidants Firming Daily Treatment

This anti-aging serum is formulated around Carnosine and Palmitoyl Tripeptide-5 to soften the look of wrinkles and refine skin texture.

This anti-aging moisturizer is formulated around Niacinamide and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and calm redness.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Butylene Glycol

Inulin

Sodium Hyaluronate

Panthenol

Alpha-Glucan Oligosaccharide

Carnosine

Carbomer

Polysorbate 20

Caprylyl Glycol

Phenoxyethanol

Hydroxypropyl Cyclodextrin

Dunaliella Salina Extract

Ethylhexylglycerin

Citric Acid

Palmitoyl Tripeptide-5

Sodium Benzoate

Acetyl Hexapeptide-8

Tetrapeptide-21

Pentapeptide-18

Palmitoyl Tripeptide-1

Pantolactone

Palmitoyl Tripeptide-38

Palmitoyl Tetrapeptide-7

Glyceryl Caprylate

Lactic Acid/Glycolic Acid Copolymer

Polyvinyl Alcohol

Phenylpropanol

Copper Palmitoyl Heptapeptide-14

Heptapeptide-15 Palmitate

Potassium Sorbate

Xanthan Gum

Water, Glycerin, Butylene Glycol, Inulin, Sodium Hyaluronate, Panthenol, Alpha-Glucan Oligosaccharide, Carnosine, Carbomer, Polysorbate 20, Caprylyl Glycol, Phenoxyethanol, Hydroxypropyl Cyclodextrin, Dunaliella Salina Extract, Ethylhexylglycerin, Citric Acid, Palmitoyl Tripeptide-5, Sodium Benzoate, Acetyl Hexapeptide-8, Tetrapeptide-21, Pentapeptide-18, Palmitoyl Tripeptide-1, Pantolactone, Palmitoyl Tripeptide-38, Palmitoyl Tetrapeptide-7, Glyceryl Caprylate, Lactic Acid/Glycolic Acid Copolymer, Polyvinyl Alcohol, Phenylpropanol, Copper Palmitoyl Heptapeptide-14, Heptapeptide-15 Palmitate, Potassium Sorbate, Xanthan Gum

Caprylic/Capric Triglyceride

Isononyl Isononanoate

Caffeine

C12-15 Alkyl Benzoate

Niacinamide

Lactobacillus Ferment

Cetearyl Olivate

Polysorbate 60

Tetrahexyldecyl Ascorbate

Marrubium Vulgare Extract

Plantago Lanceolata Leaf Extract

Acetyl Tetrapeptide-40

Palmitoyl Tripeptide-8

Hydrolyzed Verbascum Thapsus Flower

Moringa Oleifera Seed Extract

Teprenone

Phospholipids

Hyaluronic Acid

Syringa Vulgaris Leaf Cell Culture Extract

Sphingolipids

Astaxanthin

Bisabolol

Euterpe Oleracea Fruit Oil

Rubus Idaeus Seed Oil

Honey

Dimethyl Isosorbide

Ceramide NP

Phenyl T-Butylnitrone

Tocopherol

Glutathione

Tetrahydrodiferuloylmethane

Tetrahydrodemethoxydiferuloylmethane

Tetrahydrobisdemethoxydiferuloylmethane

Ergothioneine

Sorbitan Olivate

Benzimidazole Diamond Amidoethyl Urea Carbamoyl Propyl Polymethylsilsesquioxane

Mica

Dextran

Sodium Hydroxide

Acrylamide/Sodium Acryloyldimethyltaurate Copolymer

CI 77891

Isohexadecane

Maltodextrin

Polysorbate 80

Acetyl Tributyl Citrate

Tetrasodium EDTA

Sorbitan Oleate

Sodium Glycolate

O-Cymen-5-Ol

Water, Glycerin, Caprylic/Capric Triglyceride, Isononyl Isononanoate, Caffeine, C12-15 Alkyl Benzoate, Niacinamide, Lactobacillus Ferment, Cetearyl Olivate, Butylene Glycol, Polysorbate 60, Tetrahexyldecyl Ascorbate, Marrubium Vulgare Extract, Plantago Lanceolata Leaf Extract, Palmitoyl Tripeptide-5, Acetyl Tetrapeptide-40, Palmitoyl Tripeptide-8, Hydrolyzed Verbascum Thapsus Flower, Moringa Oleifera Seed Extract, Teprenone, Phospholipids, Hyaluronic Acid, Syringa Vulgaris Leaf Cell Culture Extract, Sphingolipids, Astaxanthin, Bisabolol, Euterpe Oleracea Fruit Oil, Rubus Idaeus Seed Oil, Honey, Dimethyl Isosorbide, Ceramide NP, Phenyl T-Butylnitrone, Tocopherol, Glutathione, Tetrahydrodiferuloylmethane, Tetrahydrodemethoxydiferuloylmethane, Tetrahydrobisdemethoxydiferuloylmethane, Ergothioneine, Xanthan Gum, Caprylyl Glycol, Carbomer, Sorbitan Olivate, Benzimidazole Diamond Amidoethyl Urea Carbamoyl Propyl Polymethylsilsesquioxane, Mica, Dextran, Citric Acid, Sodium Hydroxide, Acrylamide/Sodium Acryloyldimethyltaurate Copolymer, CI 77891, Ethylhexylglycerin, Isohexadecane, Maltodextrin, Polysorbate 80, Acetyl Tributyl Citrate, Tetrasodium EDTA, Sorbitan Oleate, Sodium Benzoate, Potassium Sorbate, Sodium Glycolate, Polysorbate 20, Phenoxyethanol, O-Cymen-5-Ol

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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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though 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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

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.

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.

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.

Palmitoyl Tripeptide-5 is a synthetic signal lipopeptide. This just means it is a three amino acid chain bolted onto a palmitic acid tail so it can slip through the skin's lipid barrier.

This peptide has a "build more, lose less" approach.

It's designed to mimic the collagen-stimulating activity in your skin by copying a snippet of one of your skin's own matrix proteins. This nudges fibroblasts into making more collagen while inhibiting the enzyme that breaks down skin protein.

The manufacturer's in vivo study of 45 volunteers found 1% and 2.5% reduced the appearance of wrinkles by 7% and 12% respectively, after using it twice daily for 84 days.

This is in the expected range for peptides; they're slow and cumulative actives and not overnight fixers.

Typical use levels range from 1-3% and this ingredient gets along with pretty much everything.

On the fungal acne front: Although palmitic acid sits in the chain length that Malassezia can feed on, this ingredient has it locked in an amine bond. This makes it hard for Malassezia to access as a source of food, and therefore 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.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

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 Side-by-side

  1. 01Water
  2. 02Glycerin
  3. 03Butylene Glycol
  4. 04Inulin
  5. 05Sodium Hyaluronate
  6. 06Panthenol
  7. 07Alpha-Glucan Oligosaccharide
  8. 08Carnosine
  9. 09Carbomer
  10. 10Polysorbate 20
  11. 11Caprylyl Glycol
  12. 12Phenoxyethanol
  13. 13Hydroxypropyl Cyclodextrin
  14. 14Dunaliella Salina Extract
  15. 15Ethylhexylglycerin
  16. 16Citric Acid
  17. 17Palmitoyl Tripeptide-5
  18. 18Sodium Benzoate
  19. 19Acetyl Hexapeptide-8
  20. 20Tetrapeptide-21
Source · skinsort.com
02

Product index

Related product references

Product

Medik8 Liquid Peptides (2021)

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Source: incidecoder.comView reference →

Product

Medik8 Liquid Peptides

Medik8 Liquid Peptides Ingredients in Medik8 Liquid Peptides explained: benefits, concerns, and detailed analysis of 33 ingredients including Water, Glycerin, and Butylene Glycol A highly r…

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Medik8 Liquid Peptides Medik8 Liquid Peptides ingredients explained: Aqua (Water), Glycerin, Butylene Glycol, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1, Copper Heptapeptide-14 Pantot…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side