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Peter Thomas Roth Peptide Skinjection Moisture Infusion Cream Versus Peter Thomas Roth Ultimate Solution 5 Multitasking Moisturizer

Peter Thomas Roth Peptide Skinjection Moisture Infusion Cream Versus Peter Thomas Roth Ultimate Solution 5 Multitasking Moisturizer This anti-aging moisturizer is formulated around Squalane and Hexapeptide-11 to soften the look of wrinkles and hydrate skin. Th

Peter Thomas Roth Peptide Skinjection Moisture Infusion Cream Versus Peter Thomas Roth Ultimate Solution 5 Multitasking Moisturizer

This anti-aging moisturizer is formulated around Squalane and Hexapeptide-11 to soften the look of wrinkles and hydrate skin.

This anti-aging moisturizer is formulated around Glycolic Acid and Acetyl Hexapeptide-8 to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Dimethicone

Olive Oil Decyl Esters

Glycereth-26

Squalane

Butylene Glycol

Behenyl Alcohol

Polysilicone-11

Batyl Alcohol

Simmondsia Chinensis Seed Oil

Hexapeptide-11

Dipeptide Diaminobutyroyl Benzylamide Diacetate

Palmitoyl Tripeptide-5

Tripeptide-10 Citrulline

Acetyl Hexapeptide-1

Acetyl Tetrapeptide-11

Acetyl Hexapeptide-8

Palmitoyl Hexapeptide-12

Acetyl Tetrapeptide-9

Palmitoyl Tetrapeptide-7

Acetyl Tetrapeptide-2

Acetyl Octapeptide-3

Palmitoyl Hexapeptide-19

Trifluoroacetyl Tripeptide-2

Tripeptide-1

Palmitoyl Oligopeptide

Palmitoyl Tripeptide-1

Natto Gum

Sodium Polyglutamate

Squalene

Mica

Sodium Hyaluronate

Sorbic Acid

Tocopherol

Cereus Grandiflorus Flower Extract

Pseudoalteromonas Ferment Extract

Leuconostoc/Radish Root Ferment Filtrate

Magnesium Chloride

Phenoxyethanol

Cetyl Alcohol

Stearyl Alcohol

Trehalose

Glyceryl Stearate

Silanetriol Trehalose Ether

Mannitol

Phytosterols

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Caprylic/Capric Triglyceride

Hydrogenated Lecithin

Polyglyceryl-10 Myristate

Polysorbate 20

Dimethyl Isosorbide

Sodium Benzoate

Potassium Sorbate

Caprylyl Glycol

Sodium Hydroxide

Laureth-12

Hydrolyzed Wheat Protein

Lecithin

Disodium Phosphate

Hydrolyzed Soy Protein

Carbomer

Dextran

Ethylhexylglycerin

Sodium Lactate

Tetradecyl Aminobutyroylvalylaminobutyric Urea Trifluoroacetate

Sodium Phosphate

Xanthan Gum

Triethanolamine

Acrylates Copolymer

Water, Glycerin, Dimethicone, Olive Oil Decyl Esters, Glycereth-26, Squalane, Butylene Glycol, Behenyl Alcohol, Polysilicone-11, Batyl Alcohol, Simmondsia Chinensis Seed Oil, Hexapeptide-11, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Palmitoyl Tripeptide-5, Tripeptide-10 Citrulline, Acetyl Hexapeptide-1, Acetyl Tetrapeptide-11, Acetyl Hexapeptide-8, Palmitoyl Hexapeptide-12, Acetyl Tetrapeptide-9, Palmitoyl Tetrapeptide-7, Acetyl Tetrapeptide-2, Acetyl Octapeptide-3, Palmitoyl Hexapeptide-19, Trifluoroacetyl Tripeptide-2, Tripeptide-1, Palmitoyl Oligopeptide, Palmitoyl Tripeptide-1, Natto Gum, Sodium Polyglutamate, Squalene, Mica, Sodium Hyaluronate, Sorbic Acid, Tocopherol, Cereus Grandiflorus Flower Extract, Pseudoalteromonas Ferment Extract, Leuconostoc/Radish Root Ferment Filtrate, Magnesium Chloride, Phenoxyethanol, Cetyl Alcohol, Stearyl Alcohol, Trehalose, Glyceryl Stearate, Silanetriol Trehalose Ether, Mannitol, Phytosterols, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Caprylic/Capric Triglyceride, Hydrogenated Lecithin, Polyglyceryl-10 Myristate, Polysorbate 20, Dimethyl Isosorbide, Sodium Benzoate, Potassium Sorbate, Caprylyl Glycol, Sodium Hydroxide, Laureth-12, Hydrolyzed Wheat Protein, Lecithin, Disodium Phosphate, Hydrolyzed Soy Protein, Carbomer, Dextran, Ethylhexylglycerin, Sodium Lactate, Tetradecyl Aminobutyroylvalylaminobutyric Urea Trifluoroacetate, Sodium Phosphate, Xanthan Gum, Triethanolamine, Acrylates Copolymer

Butyrospermum Parkii Butter

Cocos Nucifera Oil

Glycolic Acid

C12-15 Alkyl Benzoate

Isocetyl Stearate

Propylene Glycol Stearate

Panthenol

Tocopheryl Acetate

Methyldihydrojasmonate

Copper Palmitoyl Heptapeptide-14

Heptapeptide-15 Palmitate

Maleic Acid

Lactic Acid

Tartaric Acid

Salicylic Acid

Bisabolol

Persea Gratissima Oil

Foeniculum Vulgare Seed Extract

Ceramide NP

Collagen

Jojoba Esters

Ascorbic Acid

Helianthus Annuus Seed Wax

Sodium Phytate

Cholesterol

Macrocystis Pyrifera Extract

Echinacea Angustifolia Extract

Camellia Oleifera Leaf Extract

Camellia Sinensis Leaf Extract

Vitis Vinifera Seed Extract

Centella Asiatica Extract

Acacia Decurrens Flower Wax

Polyglycerin-3

Stearic Acid

Lactic Acid/Glycolic Acid Copolymer

Sorbitan Isostearate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Methylpropanediol

Polyvinyl Alcohol

Ascorbyl Methylsilanol Pectinate

Isohexadecane

Histidine Hcl

Stearoxytrimethylsilane

Viola Tricolor Extract

Polysorbate 60

Water, Glycerin, Butyrospermum Parkii Butter, Glyceryl Stearate, Cocos Nucifera Oil, Glycolic Acid, C12-15 Alkyl Benzoate, Isocetyl Stearate, Cetyl Alcohol, Propylene Glycol Stearate, Dimethicone, Sodium Hydroxide, Butylene Glycol, Panthenol, Tocopheryl Acetate, Methyldihydrojasmonate, Copper Palmitoyl Heptapeptide-14, Heptapeptide-15 Palmitate, Acetyl Hexapeptide-8, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-5, Maleic Acid, Lactic Acid, Tartaric Acid, Salicylic Acid, Bisabolol, Persea Gratissima Oil, Foeniculum Vulgare Seed Extract, Ceramide NP, Collagen, Jojoba Esters, Ascorbic Acid, Sodium Hyaluronate, Helianthus Annuus Seed Wax, Sodium Phytate, Cholesterol, Macrocystis Pyrifera Extract, Echinacea Angustifolia Extract, Camellia Oleifera Leaf Extract, Camellia Sinensis Leaf Extract, Vitis Vinifera Seed Extract, Centella Asiatica Extract, Acacia Decurrens Flower Wax, Polyglycerin-3, Carbomer, Sodium Lactate, Stearic Acid, Leuconostoc/Radish Root Ferment Filtrate, Lactic Acid/Glycolic Acid Copolymer, Sorbitan Isostearate, Potassium Sorbate, Polysorbate 20, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Methylpropanediol, Ethylhexylglycerin, Polyvinyl Alcohol, Ascorbyl Methylsilanol Pectinate, Isohexadecane, Polysilicone-11, Histidine Hcl, Stearyl Alcohol, Stearoxytrimethylsilane, Xanthan Gum, Viola Tricolor Extract, Sodium Benzoate, Polysorbate 60, Phenoxyethanol

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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.

Acetyl Hexapeptide-8 (also known as Argireline) is a synthetic hexapeptide that is often called a "topical Botox alternative".

It works by mimicking how Botox relaxes muscles; it interferes with the signaling process that tells your facial muscles to contract. This can help soften expression lines like forehead wrinkles or crow's feet over time.

The comparison to Botox does have limits because the molecule is water-loving and relatively large.

Acetyl Hexapeptide-8 has a hard time absorbing deeply enough through the skin's outer barrier to actually reach the muscles.

So whether it truly works the way Botox does at a biological level is still up for debate, but early clinical outcomes are fairly encouraging.

A 12 week human study of a multi-ingredient regimen containing this ingredient saw:

While some studies have observed improvements in wrinkle appearance, it is important to note that more consistent results are seen in multi-ingredient formulations (vs just Acetyl Hexapeptide-8 alone).

Some research studies also used higher concentrations (up to 10%) while this ingredient is usually found in concentrations up to 0.005% in leave-on formulations.

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.

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.

Cetyl Alcohol is a fatty alcohol. Fatty Alcohols are most often used as an emollient or to thicken a product.

Its main roles are:

Though it has "alcohol" in the name, it is not related to denatured alcohol or ethyl alcohol.

The FDA allows products labeled "alcohol-free" to have fatty alcohols.

This ingredient may not be fungal acne safe. It is a primary fatty alcohol with a chain length above 12 carbons. A study from 2019 show Malassezia can feed on fatty alcohols in this range, so it may trigger fungal acne in those prone to it.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This 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.

Note: 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.

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.

Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.

Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.

This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

Leuconostoc/Radish Root Ferment Filtrate is a natural preservative. It comes from fermenting radish roots with a bacteria called leuconostoc. The trade name for this ingredient is Leucidal.

Leuconostoc comes from lactic acid.

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

Palmitoyl Tetrapeptide-7 (formerly Palmitoyl Tetrapeptide-3) is a synthetic peptide. Its main job is to fight what researchers call "inflammaging".

"Inflammaging" is the slow, low-grade chronic inflammation that quietly breaks down collagen as we age.

This ingredient calms down a specific inflammation signal in your skin cells (called IL-6). When left unchecked, this signal triggers enzymes that break down collagen and elastin.

Clinical testing showed statistically significant improvements in:

Studies also found the more of this ingredient used, the more your skin produces Collagen I, fibronectin, and hyaluronic acid.

You'll likely see this ingredient paired with Palmitoyl Tripeptide-1 in the well-known Matrixyl 3000 complex for enhanced anti-aging effects.

A 3% concentration applied twice daily for two months showed meaningful skin rejuvenation results in clinical panels.

Fungal acne note: Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

Palmitoyl Tripeptide-1 (aka Pal-GHK) is a synthetic signal peptide made of three amino acids attached to palmitic acid.

That fatty acid attachment is the key: it boosts the peptide's ability to penetrate the skin barrier. This puts it closer to the dermal cells where it can actually make a difference.

Once there, it acts as a matrikine, a signaling peptide that prompts fibroblasts to produce more collagen, fibronectin, and hyaluronic acid.

In vitro studies show it can boost collagen production in skin cells even when UV-damaged skin samples were treated with it at a tiny concentration (it almost fully restored dermal collagen at 5ppm). It achieved this at 100x lower concentration than retinoic acid, which needed 500 ppm to do the same thing.

Human clinical data is promising, but modest:

A study of 23 female volunteers found a small but statistically significant increase (~4%) in skin thickness after treatment at 4 ppm.

A separate small trial of 15 women showed statistically significant reductions in wrinkle length, depth, and skin roughness after applying it twice daily for four weeks.

You'll likely see Pal-GHK paired with Palmitoyl Tetrapeptide-7 as part of the Matrixyl 3000 complex.

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.

Polysilicone-11 is a film-forming silicone that creates a non-tacky and matte finish on the skin. It's commonly used to improve texture, absorb excess oil, and help active ingredients spread evenly.

Due to its "rubber-like" structure, it stays on the skin's surface instead of being absorbed. On the skin, it creates a flexible layer that enhances wearability and stability.

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.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

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.

Sodium Lactate is the sodium salt of lactic acid, an AHA. It is a humectant and sometimes used to adjust the pH of a product.

This ingredient is part of our skin's NMF, or natural moisturizing factor. Our NMF is essential for the hydration of our top skin layers and plasticity of skin. NMF also influences our skin's natural acid mantle and pH, which protects our skin from harmful bacteria.

High percentages of Sodium Lactate can have an exfoliating effect.

Fun fact: Sodium Lactate is produced from fermented sugar.

Stearyl Alcohol is a type of fatty alcohol from stearic acid. It is a white, waxy compound used to emulsify ingredients used as an emollient or to thicken a product.

Emollients help soothe and hydrate the skin by trapping moisture.

Fatty alcohols are usually derived from natural fats and oils and therefore do not have the same drying or irritating effect as solvent (ethanol) alcohols.

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.

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