La Roche-Posay Effaclar Duo (+)
A facial treatment with 29 ingredients, including BHA, niacinamide, and exfoliants.
Overview
What it is
Facial treatment with 29 ingredients that contains BHA, exfoliants, niacinamide and zinc
Suited For
It has ingredients that are good for fighting acne, anti aging, dry skin, brightening skin, sensitive skin, oily skin, reducing pores, scar healing, dark spots and better texture
Free From
It doesn't contain any harsh alcohols, common allergens, oils, parabens or sulfates
Fun facts
La Roche-Posay is from France.
We independently verify ingredients and our claims are backed by peer-reviewed research. Does this product need an update? Let us know.
What's inside
Ingredients List
Water
Skin ConditioningGlycerin
HumectantDimethicone
EmollientIsocetyl Stearate
EmollientNiacinamide
SmoothingIsopropyl Lauroyl Sarcosinate
Skin ConditioningSilica
AbrasiveAmmonium Polyacryloyldimethyl Taurate
Emulsion StabilisingMethyl Methacrylate Crosspolymer
Potassium Cetyl Phosphate
EmulsifyingZinc PCA
HumectantGlyceryl Stearate Se
EmulsifyingIsohexadecane
EmollientSodium Hydroxide
BufferingMyristyl Myristate
Emollient2-Oleamido-1,3-Octadecanediol
Skin ConditioningNylon-12
Poloxamer 338
EmulsifyingLinoleic Acid
CleansingDisodium EDTA
Capryloyl Salicylic Acid
ExfoliatingCaprylyl Glycol
EmollientXanthan Gum
EmulsifyingPolysorbate 80
EmulsifyingAcrylamide/Sodium Acryloyldimethyltaurate Copolymer
Emulsion StabilisingPentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate
AntioxidantSalicylic Acid
MaskingPiroctone Olamine
PreservativeParfum
MaskingWater, Glycerin, Dimethicone, Isocetyl Stearate, Niacinamide, Isopropyl Lauroyl Sarcosinate, Silica, Ammonium Polyacryloyldimethyl Taurate, Methyl Methacrylate Crosspolymer, Potassium Cetyl Phosphate, Zinc PCA, Glyceryl Stearate Se, Isohexadecane, Sodium Hydroxide, Myristyl Myristate, 2-Oleamido-1,3-Octadecanediol, Nylon-12, Poloxamer 338, Linoleic Acid, Disodium EDTA, Capryloyl Salicylic Acid, Caprylyl Glycol, Xanthan Gum, Polysorbate 80, Acrylamide/Sodium Acryloyldimethyltaurate Copolymer, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Salicylic Acid, Piroctone Olamine, Parfum
Key Ingredients
Benefits
Concerns
Ingredients Explained
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!
Learn more about WaterGlycerin (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.
Learn more about GlycerinDimethicone 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.
Learn more about DimethiconeIsocetyl Stearate is an ester of isocetyl alcohol and stearic acid.
Stearate esters are low in viscosity and are oily by nature. Once applied, these stearate esters create a film on your skin. As an emollient, Isocetyl Stearate helps soften and smooth your skin.
One study found Isocetyl Stearate is non-irritating to human skin. However, another study found Isocetyl Stearate to be pore-clogging or comedogenic.
Learn more about Isocetyl StearateNiacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.
And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.
You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.
In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.
If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.
When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.
When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.
In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).
Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.
Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.
The type of niacinamide used in skincare is synthetically created.
Learn more about NiacinamideWe don't have a description for Isopropyl Lauroyl Sarcosinate yet.
Silica, also known as silicon dioxide, is a naturally occurring mineral. It is used as a fine, spherical, and porous powder in cosmetics.
Though it has exfoliant properties, the function of silica varies depending on the product.
The unique structure of silica enhances the spreadability and adds smoothness, making it a great texture enhancer.
It is also used as an active carrier, emulsifier, and mattifier due to its ability to absorb excess oil.
In some products, tiny microneedles called spicules are made from silica or hydrolyzed sponge. When you rub them in, they lightly polish away dead skin layers and enhance the penetration of active ingredients.
Learn more about SilicaAmmonium Polyacryloyldimethyl Taurate is a polymer made from ammonium salts. It works as a thickener, emulsifier, and texture enhancer that gives gel-creams a silky, lightweight feel.
This ingredient is versatile and low-maintenance so manufacturers love working with it.
Typical usage levels in cosmetics are usually low and in the range of 0.015 - 2.3%.
Learn more about Ammonium Polyacryloyldimethyl TaurateThis ingredient comes as a powder made up of small, porous, microbeads. It is used to add a silky feel to products and also helps absorb oil.
Potassium Cetyl Phosphate is the potassium salt of a mixture. This mixture consists of the esters from phosphoricacid and cetyl alcohol.
Potassium Cetyl Phosphate is an emulsifier and cleansing agent. Emulsifiers help stabilize a product. It does this by preventing certain ingredients from separating.
As a cleansing agent, Potassium Cetyl Phosphate helps gather oils, dirts, and pollutants from your skin. This makes it easier to rinse them away with water.
Learn more about Potassium Cetyl PhosphateZinc PCA (or "zinc salt") differs slightly from zinc itself. PCA stands for pyrrolidone carboxylic acid. However, Zinc PCA comes from zinc.
It can help reduce redness, regulate sebum, and promote the general healing process of the skin.
Zinc PCA tends to be especially useful for those with oily, acne-prone skin. It's certainly an ingredient worth trying out!
Learn more about Zinc PCAGlyceryl Stearate Se is a self-emulsifying (SE) form of glyceryl stearate. Self-emusifying means this ingredient automatically blends with water. It is an emulsifier, emollient, and cleansing agent.
As an emulsifier, Glyceryl Stearate Se prevents ingredients such as oil and water from separating. It is also a surfactant, meaning it helps cleanse the skin. Surfactants help gather oil, dirt, and other pollutants so they may be rinsed away easily.
Emollients help your skin stay smooth and soft. It does so by creating a film on top of the skin that helps trap moisture in.
Learn more about Glyceryl Stearate SeIsohexadecane is added to enhance texture, emulsify, and to help cleanse. It is an isoparrafin. It is a component of petrolatum.
Due to its large size, Isohexadecane is not absorbed by the skin. Instead, it sits on top and acts as an emollient. Emollients help keep your skin soft and smooth by trapping moisture within.
Isohexadecane is often used in products designed to help oily skin. It is lightweight and non-greasy while helping to moisturize. When mixed with silicones, it gives a product a silky feel.
Learn more about IsohexadecaneSodium 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.
Learn more about Sodium HydroxideMyristyl Myristate is created from the fatty acids of myristyl alcohol and myristic acid. In skincare, it is an emollient and texture enhancer.
On its own, this ingredient has a comedogenicity index of 5/5. This means it has the potential to clog pores. When diluted with cetyl alcohol or propylene glycol, the comedogenicity will decrease.
This ingredient may not be Malassezia folliculitis, or fungal-acne safe.
Nutmeg, palm kernel oil, and coconut oil all contain this ingredient naturally.
Learn more about Myristyl MyristateWe don't have a description for 2-Oleamido-1,3-Octadecanediol yet.
Nylon-12 is a polymer. It is derived from 12-aminododecanoic acid, an omega-amino fatty acid
According to a manufacturer, it is a talc substitute. Like talc, nylon-12 gives products a satin feel. The manufacturer also claims this ingredients does not block pores and has moderate oil absorption.
This ingredient may not be reef-safe.
Learn more about Nylon-12We don't have a description for Poloxamer 338 yet.
Linoleic Acid is also known as Vitamin F. It is a fatty acid with emollient and skin conditioning properties.
Our top layer of skin, or epidermis, naturally contains high amounts of linoleic acid.
Your body uses linoleic acid to build ceramides and prostaglandins. Ceramides keep your skin's barrier hydrated and strong while prosaglandins help control inflammation and healing.
Needless to say, linoleic acid is crucial for having a strong skin barrier.
One study found applying linoleic acid rich sunflower oil to be more effective at repairing the skin barrier than olive oil.
This ingredient can also help treat acne by softening sebum to prevent clogged pores. Another study found using 2.5% linoleic acid gel for 4 weeks showed a 25% reduction in small comedones.
Studies show it can also help lighten hyperpigmentation or sun spots by disrupting the melanin production process. It also helps your skin shed melanin pigment from your skin caused by UV exposure.
Due to its role in the production of the fatty acid prostaglandin, linoleic acid can also help reduce inflammation and support wound healing.
Fun fact: Linoleic acid is an essential fatty acid. This means our bodies cannot create it on its own and we need to get it through foods such as nuts and vegetable oils.
Just know this ingredient is not always fungal-acne safe because it is a long-chain fatty acid (with 18 carbon atoms) that directly feeds the Malassezia yeast responsible for fungal acne.
Learn more about Linoleic AcidDisodium 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%.
Learn more about Disodium EDTACapryloyl Salicylic Acid comes from salicylic acid, the famous acne-fighting BHA.
It usually goes by a more common name of LHA, or lipohydroxy acid.
Like salicylic acid, this ingredient is a chemical exfoliant that can help break down the oil in your pores and reduce inflammation.
Though studies for LHA do show it to be less effective than salicylic acid. To be fair, salicylic acid is the reigning monarch of acne treatments.
However, a study from 2009 found LHA to be comparable to BPO, making it a good alternative for people with sensitive skin. Another study of 14 patients found a significant decrease in comedones after using LHA.
Another pro of LHA? It is less irritating than salicylic acid due to its large molecule size.
Large molecules cannot penetrate skin as well, so they are gentler on the skin. LHA is much less penetrative than salicylic acid.
An in-vitro study (not done on a living organism) found only 6% of LHA penetrated past the statum corneum compared to 58% of salicylic acid. An in-vivo (done on a living organism) analysis revealed ~17% of LHA was still present in the top layer of skin after 4 days, versus ~9% of salicylic acid.
Interestingly, a study from 2008 found LHA comparable to another famous acid, glycolic acid.
This study found about 10% of LHA is as effective as 20-50% of glycolic acid in treating hyperpigmentation and fine-lines.
Hydroxy acids have been found to stimulate skin protein, lipids, and thermal thickening. This may have anti-aging benefits.
Learn more about Capryloyl Salicylic AcidCaprylyl 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 or alcohol, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
Learn more about Caprylyl GlycolXanthan 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.
Learn more about Xanthan GumPolysorbate 80 is a synthetic surfactant and emulsifier derived from sorbitol and oleic acid.
It reduces the surface tension between oil and water phases to help them stay mixed and stable in a formulation. In other words, it prevents your formulas from separating into an oily mess.
The CIR Expert Panel has evaluated the scientific data and found this ingredient to be safe, non-irritating, and non-sensitizing at concentrations up to 5% (it's even approved by the FDA as an OTC eye drop ingredient).
Learn more about Polysorbate 80This ingredient is a synthetic polymer used to stabilize formulas and give products a "gel-cream" feel.
When applied, this ingredient mostly stays on the surface of skin. Safety reviews have found these polymers safe in cosmetics when made to proper quality standards. Testing also shows they’re unlikely to cause irritation or sensitization at normal use levels.
Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate (long name, huh?) is a synthetic antioxidant.
It is used to help stabilize other antioxidants or prevent the color from changing in a product.
As an antioxidant, it helps fight free-radical molecules. Free-radical molecules are capable of damaging our cells and other genetic material. Thus, antioxidants may reduce the signs of aging.
This ingredient is oil-soluble.
Learn more about Pentaerythrityl Tetra-Di-T-Butyl HydroxyhydrocinnamateSalicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, and reduce inflammation.
Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.
Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.
Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.
It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.
While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.
If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.
Learn more about Salicylic AcidPiroctone Olamine targets Malassezia, the fungus responsible for dandruff, which is why you'll find it in many anti-dandruff shampoos.
It's also water-soluble, so it blends easily into these formulas.
Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.
For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.
The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.
One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Parfum can also be used to mask or cover an unpleasant scent.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
Learn more about ParfumReviews
Where it's from
La Roche-Posay is a French brand
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The data we've presented on this page has been verified by a member of the SkinSort Team.
Read more about us· Updated May 19, 2026 • Added by CatarinaCarrilho_426