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Dr. Althea Rapid Firm Sculpting Cream Versus MEDI-PEEL Peptide 9 Volume Tox Cream

Dr. Althea Rapid Firm Sculpting Cream Versus MEDI-PEEL Peptide 9 Volume Tox Cream This anti-aging moisturizer is formulated around Hydroxydecyl Ubiquinone and Copper Tripeptide-1 to soften the look of wrinkles. This anti-aging moisturizer is formulated around

Dr. Althea Rapid Firm Sculpting Cream Versus MEDI-PEEL Peptide 9 Volume Tox Cream

This anti-aging moisturizer is formulated around Hydroxydecyl Ubiquinone and Copper Tripeptide-1 to soften the look of wrinkles.

This anti-aging moisturizer is formulated around Adenosine and Acetyl Hexapeptide-8 to soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Caprylic/Capric Triglyceride

Glycerin

Butylene Glycol

Cetearyl Alcohol

Polyglyceryl-3 Methylglucose Distearate

Cyclopentasiloxane

Polysorbate 60

Glyceryl Stearate

Palmitic Acid

1,2-Hexanediol

Cyclohexasiloxane

Dimethicone

Benzyl Glycol

Stearic Acid

Sorbitan Sesquioleate

Ethylhexylglycerin

Carbomer

Arginine

Sodium Polyacrylate

Isopentyldiol

Tocopheryl Acetate

Allantoin

Propanediol

Dipotassium Glycyrrhizate

Polyglyceryl-4 Oleate

Disodium EDTA

Hydrolyzed Corn Starch

Sucrose Palmitate

Dipropylene Glycol

Leontopodium Alpinum Extract

Lauric Acid

Hydroxydecyl Ubiquinone

Sucrose

Myristic Acid

Citrus Aurantium Bergamia Fruit Oil

Anastatica Hierochuntica Extract

Butyrospermum Parkii Butter

Hydrolyzed Collagen

Silk Extract

Salmon Egg Extract

Beta-Glucan

Adansonia Digitata Fruit Extract

Hydrolyzed Glycosaminoglycans

Sodium Hyaluronate

Sodium Hyaluronate Crosspolymer

Copper Tripeptide-1

Hydrolyzed Hyaluronic Acid

Acetyl Hexapeptide-8

Hydroxypropyltrimonium Hyaluronate

Hyaluronic Acid

Sodium Acetylated Hyaluronate

Water, Caprylic/Capric Triglyceride, Glycerin, Butylene Glycol, Cetearyl Alcohol, Polyglyceryl-3 Methylglucose Distearate, Cyclopentasiloxane, Polysorbate 60, Glyceryl Stearate, Palmitic Acid, 1,2-Hexanediol, Cyclohexasiloxane, Dimethicone, Benzyl Glycol, Stearic Acid, Sorbitan Sesquioleate, Ethylhexylglycerin, Carbomer, Arginine, Sodium Polyacrylate, Isopentyldiol, Tocopheryl Acetate, Allantoin, Propanediol, Dipotassium Glycyrrhizate, Polyglyceryl-4 Oleate, Disodium EDTA, Hydrolyzed Corn Starch, Sucrose Palmitate, Dipropylene Glycol, Leontopodium Alpinum Extract, Lauric Acid, Hydroxydecyl Ubiquinone, Sucrose, Myristic Acid, Citrus Aurantium Bergamia Fruit Oil, Anastatica Hierochuntica Extract, Butyrospermum Parkii Butter, Hydrolyzed Collagen, Silk Extract, Salmon Egg Extract, Beta-Glucan, Adansonia Digitata Fruit Extract, Hydrolyzed Glycosaminoglycans, Sodium Hyaluronate, Sodium Hyaluronate Crosspolymer, Copper Tripeptide-1, Hydrolyzed Hyaluronic Acid, Acetyl Hexapeptide-8, Hydroxypropyltrimonium Hyaluronate, Hyaluronic Acid, Sodium Acetylated Hyaluronate

Methylpropanediol

Cetearyl Olivate

Sorbitan Olivate

Pentaerythrityl Tetraisostearate

PEG-100 Stearate

Cetearyl Glucoside

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Isohexadecane

Trehalose

Helianthus Annuus Seed Oil

Xanthan Gum

Adenosine

Polysorbate 80

Sorbitan Oleate

Glycine Soja Oil

Desamido Collagen

Juniperus Communis Fruit Extract

Magnolia Officinalis Bark Extract

Eucalyptus Globulus Leaf Extract

Fructan

Parfum

Hydrogenated Polyisobutene

Bixa Orellana Seed Oil

Glyceryl Polymethacrylate

Sorbitan Laurate

Propylene Glycol

Nonoxynol-14

Phenoxyethanol

Chondrus Crispus Extract

Tocopherol

Hydroxyethylcellulose

Acetyl Dipeptide-1 Cetyl Ester

Astaxanthin

Ethyl Hexanediol

Hydrolyzed Elastin

Palmitoyl Tripeptide-5

Caprylyl Glycol

Anemarrhena Asphodeloides Root Extract

Palmitoyl Pentapeptide-4

Acetyl Octapeptide-3

Palmitoyl Tetrapeptide-7

Hexapeptide-9

Raspberry Ketone

Palmitoyl Oligopeptide

Palmitoyl Tripeptide-1

Water, Methylpropanediol, Glycerin, Dimethicone, Cyclopentasiloxane, 1,2-Hexanediol, Caprylic/Capric Triglyceride, Cetearyl Alcohol, Cetearyl Olivate, Cyclohexasiloxane, Sorbitan Olivate, Glyceryl Stearate, Pentaerythrityl Tetraisostearate, PEG-100 Stearate, Cetearyl Glucoside, Arginine, Carbomer, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Isohexadecane, Trehalose, Helianthus Annuus Seed Oil, Xanthan Gum, Adenosine, Polysorbate 80, Sodium Hyaluronate, Disodium EDTA, Sorbitan Oleate, Glycine Soja Oil, Desamido Collagen, Juniperus Communis Fruit Extract, Magnolia Officinalis Bark Extract, Eucalyptus Globulus Leaf Extract, Fructan, Hydrolyzed Collagen, Butylene Glycol, Parfum, Hydrogenated Polyisobutene, Bixa Orellana Seed Oil, Propanediol, Glyceryl Polymethacrylate, Sodium Hyaluronate Crosspolymer, Sorbitan Laurate, Propylene Glycol, Hydrolyzed Glycosaminoglycans, Nonoxynol-14, Phenoxyethanol, Chondrus Crispus Extract, Tocopherol, Hydroxyethylcellulose, Benzyl Glycol, Acetyl Dipeptide-1 Cetyl Ester, Astaxanthin, Ethyl Hexanediol, Hydrolyzed Elastin, Hydrolyzed Hyaluronic Acid, Ethylhexylglycerin, Palmitoyl Tripeptide-5, Caprylyl Glycol, Anemarrhena Asphodeloides Root Extract, Acetyl Hexapeptide-8, Copper Tripeptide-1, Palmitoyl Pentapeptide-4, Hyaluronic Acid, Acetyl Octapeptide-3, Palmitoyl Tetrapeptide-7, Hexapeptide-9, Raspberry Ketone, Palmitoyl Oligopeptide, Palmitoyl Tripeptide-1

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.

It is a:

Humectant, drawing moisture into the skin

Emollient, helping to soften skin

Solvent, dispersing and stabilizing formulas

Preservative booster, enhancing the antimicrobial activity of other preservatives

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.

Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.

It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

We don't have a description for Benzyl Glycol yet.

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.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Copper Tripeptide-1 (GHK-Cu) is a skin repairing ingredient known for its ability to boost collagen, improve firmness, and support skin regeneration.

It is a complex made up of a naturally occurring peptide (glycine-histidine-lysine) and copper, an essential trace element.

While studying wound healing, researchers noticed GHK-Cu stimulated hair follicle enlargement and growth by keeping hair in its active growth phase longer. This has made it a promising ingredient for hair regrowth treatments.

Some people have reported increased facial hair. While GHK-Cu can make your hair follicles bigger, it usually doesn’t turn soft, barely-visible facial hairs into thick, dark ones.

Anecdotal reports suggest that overusing copper peptides might lead to premature aging due to excess free copper or enzyme imbalances. This claim isn’t backed by large-scale studies.

Unfortunately, there are limited human studies for this ingredient. While early results are promising, many studies are either small, in-vitro, or not rigorously controlled.

For example, there is a 1998 study that explored the effects of copper tripeptide, vitamin C, tretinoin, and melatonin on skin repair and collagen synthesis.

After one month, increased procollagen production was seen in 7 out of 10 participants using copper tripeptide (more than those using vitamin C, melatonin, or tretinoin.

While the study was exploratory, it offers early evidence that copper tripeptide may support collagen production. Larger, well-designed trials are still needed to confirm its potential and understand individual responses.

Read more about other common types of peptides here:

Cyclohexasiloxane is a type of silicone more commonly known as D6. It is an emollient and solvent.

Cyclohexasiloxane is used to evenly distribute ingredients throughout the product. When applied to the skin, Cyclohexasiloxane evaporates and leaves behind a silky feel.

As an emollient, it can help the skin feel soft and hydrated. It is also used to reduce frizz in hair products.

Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.

Since D5 is volatile, it does its thing and then evaporates off the skin quickly.

The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics

There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.

Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.

The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.

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.

Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.

This ingredient mainly works behind the scenes and helps with:

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

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.

Hyaluronic acid (HA) is a glycosaminoglycan (basically a long sugar chain) that your skin already makes on its own. In your skin, HA lives in the extracellular matrix and acts as the body's moisture reservoir.

Topically, HA is a humectant that binds water and helps skin look more plump, smooth, and hydrated.

The only catch is that HA isn't a single thing; it actually comes in a wide range of molecular weights (~50 - 2,000+ kDA) and size matters.

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

This is why the best HA serums blend the two sizes together so you get the best of both worlds.

The majority of cosmetic HA is produced by bacterial fermentation, typically using Streptococcus or Bacillus strains. Typical use levels in skincare sit around 0.1-2%.

A clinical study using a 0.2% low-molecular weight HA gel showed improvement in facial seborrheic dermatitis with excellent tolerance.

These are some other common types of Hyaluronic Acid:

Hydrolyzed Collagen is Collagen (usually sourced from fish, bovine, or porcine byproducts) that's been broken down into smaller peptides. This makes it water-soluble and easy to blend into formulations.

In a formula, it works mainly as a skin-conditioning and moisturizing agent.

The small peptides and amino acids (including Natural Moisturizing Factor components like Hydroxyproline, Serine, and Aspartic Acid) help the surface of the skin hold onto water, feel softer, and look temporarily plumper.

This ingredient also has mild film-forming and antioxidant properties with research showing the antioxidant effect is stronger the lower the molecular weight of the peptides.

It's worth being realistic here:

Topically applied Hydrolyzed Collagen conditions the upper layers of skin rather than rebuilding the structural collagen deep in your dermis (the wrinkle-and-firmness benefits people associate with Collagen mostly come from oral supplements in studies, not topicals).

However, recent lab and skin-model work on Hydrolyzed Fish Collagen has shown promising effects on cell viability and wound healing when used as an active.

Typical concentrations range from 0.2-2%, but the percentage can go much higher in rinse-off or hair products (sometimes even above 50%).

Clinical studies on this ingredient showed no irritation, sensitization, or phototoxicity.

If you are looking for vegan collagen, it usually goes by a different INCI name like hydrolyzed soy protein. Vegan collagen is derived from yeast, bacteria, or plant sources.

The results are varied.

A study from 2021 found hydrolyzed collagen increased elasticity and improved wrinkles in 1,125 participants between age 20 and 70. Another study found increased skin thickness in participants between the ages of 45 to 59.

However, It is difficult to prove that oral collagen will end up working on your skin. Many of the studies using hydrolyzed collagen also add several vitamins and nutrients into the test mixture as well.

Further studies are needed at this time.

We don't have a description for Hydrolyzed Glycosaminoglycans yet.

Hydrolyzed Hyaluronic Acid is hyaluronic acid (HA) that is broken down into lower molecular weight fragments.

It's a humectant that pulls and holds water in the skin to help with hydration, plumpness, and reduce transepidermal water loss.

Because hydrolyzed hyaluronic acid is smaller in size, it can slip past your outermost layer of skin more easily than full-sized HA.

Most formulations will combine all sizes to get the best of both worlds.

Typical usage levels range from 0.01-1%. Any percentage higher than 2% might become goopy and tacky.

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 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:

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 Hyaluronate Crosspolymer is a crosslinked version of sodium hyaluronate. This just means it's linked into a 3D mesh network that lets it be more stable and sit on skin as a cohesive, gel-like film rather than sinking into skin.

A 2016 human skin study found crosslinked HA increased epidermal water content by 7.6% over the control group and reduced transepidermal water loss by 27.8%.

A follow-up clinical trial found that a topical crosslinked HA serum applied after fillers, microneedling, or chemical peels was well-tolerated and enhanced skin quality at 14 / 28 days.

More recent research suggests that concentrations as low as 0.03% can act as a penetration enhancer for other skincare actives.

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.

02

Product index

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03

Comparison edit

Read side by side