Differin Dark Spot Correcting Serum 2% Hydroquinone Versus Differin Dark Spot Correcting Serum 4% Niacinamide
Updated on May 28, 2025
Overview
What they are
These products are both reef safe serums. They have a total of 12 ingredients in common
Suited For
They're both likely to be good for dry skin, brightening skin, oily skin, reducing pores, scar healing, dark spots and better texture
Free From
They both do not contain any common allergens, parabens, silicones or sulfates
What's Inside
They both contain harsh alcohols, fragrances and oils
We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.
Ingredient Info
Differin Dark Spot Correcting Serum 2% Hydroquinone 14 ingredients
Differin Dark Spot Correcting Serum 4% Niacinamide 23 ingredients
What's inside (and what isn't)
What's inside (and what isn't)
At a glance
Click on any of the items below to learn more
Differin Dark Spot Correcting Serum 2% Hydroquinone 14 ingredients
Differin Dark Spot Correcting Serum 4% Niacinamide 23 ingredients
Key Ingredients
Benefits
Concerns
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Skin ConditioningAlcohol
Antimicrobial
Niacinamide 4%
Smoothing
PEG-40 Hydrogenated Castor Oil
Emulsifying
Polysorbate 20
Emulsifying
Hydroxyethylcellulose
Emulsion StabilisingSodium Ascorbyl Phosphate
Antioxidant
1,2-Hexanediol
Skin Conditioning
Caprylyl Glycol
EmollientHippophae Rhamnoides Oil
Emollient
Helianthus Annuus Seed Oil
Emollient
Rosmarinus Officinalis Leaf Extract
AntimicrobialBiotin
AntiseborrhoeicSodium Metabisulfite
Antioxidant
Sodium Sulfite
Preservative
Citric Acid
Buffering
Disodium EDTA
T-Butyl Alcohol
Perfuming
Disodium Phosphate
BufferingPolysorbate 60
Emulsifying
Parfum
Masking
Sodium Phosphate
BufferingDenatonium Benzoate
Masking
Water, Alcohol, Niacinamide 4%, PEG-40 Hydrogenated Castor Oil, Polysorbate 20, Hydroxyethylcellulose, Sodium Ascorbyl Phosphate, 1,2-Hexanediol, Caprylyl Glycol, Hippophae Rhamnoides Oil, Helianthus Annuus Seed Oil, Rosmarinus Officinalis Leaf Extract, Biotin, Sodium Metabisulfite, Sodium Sulfite, Citric Acid, Disodium EDTA, T-Butyl Alcohol, Disodium Phosphate, Polysorbate 60, Parfum, Sodium Phosphate, Denatonium Benzoate
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
Caprylyl Glycol is a humectant and emollient, meaning it attracts and preserves moisture.
It is a common ingredient in many products, especially those designed to hydrate skin. The primary benefits are retaining moisture, skin softening, and promoting a healthy skin barrier.
Though Caprylyl Glycol is an alcohol derived from fatty acids, it is not the kind that can dry out skin.
This ingredient is also used as a preservative to extend the life of products. It has slight antimicrobial properties.
Learn more about Caprylyl GlycolCitric Acid is an AHA derived from citrus fruits (think oranges, lemons, and limes!).
As an AHA, Citric Acid removes the top layer of skin cells from the newer layer of skin underneath. This helps skin to remove dark spots and even out skin tone.
If you spot Citric Acid near the end of an ingredient list, it's likely there as a pH adjuster rather than an active ingredient.
Read more about some other popular AHA's here:
Learn more about Citric AcidDisodium EDTA plays a role in making products more stable by aiding other preservatives.
It is a chelating agent, meaning it neutralizes metal ions that may be found in a product.
Disodium EDTA is a salt of edetic acid and is found to be safe in cosmetic ingredients.
Learn more about Disodium EDTAHippophae Rhamnoides Oil also known as seabuckthorn oil. This oil is usually extracted from the fruit pulp or seeds.
Seabuckthorn is rich in phytosterols, carotenoids, Vitamins A, C, and E. This gives it strong antioxidant properties that can help soothe and protect your skin from oxidative damage.
This oil is rich in fatty acids, including: two types of linoleic acid (~30-34%), oleic acid (17%), and palmiteic acid (35%). Note these numbers are averages, and different parts of the plant will vary.
Palmitoleic acid has been shown to help soothe inflammation and promote wound healing. It is also naturally found in the fat of our skin.
Overall, seabuckthorn oil is great for nourishing, hydrating, and soothing skin. While it shows UV protecting properties, it should not replace sunscreen.
Due to the rich fatty acid content, this ingredient may not be Malassezia folliculitis, or fungal acne, safe.
Seabuckthorn berries are little orange fruits. This plant is native to Asia.
Learn more about Hippophae Rhamnoides OilHydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.
This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.
This ingredient can also be found in pill medicines to help our bodies digest other ingredients.
Learn more about HydroxyethylcelluloseParfum 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 ParfumPeg-40 Hydrogenated Castor Oil is derived from castor oil and polyethylene glycol (PEG). It is used as a emollient and emulsifier.
As an emulsifier, it helps prevent ingredients from separating. It also helps make the other ingredients more soluble; it is often used to solubilize fragrances. This increases spreadability and elongates shelf life in a product.
Emollients help soothe and soften the skin. They do this by creating a protective film on your skin. This barrier helps trap moisture and keeps your skin hydrated. Emollients may be effective at treating dry or itchy skin.
This ingredient may or may not be vegan, depending on the source.
Peg-40 Hydrogenated Castor Oil may not be fungal-acne safe. We recommend speaking with a professional if you have any questions or concerns.
Learn more about PEG-40 Hydrogenated Castor OilPolysorbate 20 is made by combining ethoxylation of sorbitan, ethylene oxide, and lauric acid. It is a mild cleansing agent, surfactant, and emulsifier.
As a surfactant, it helps collect dirt and oils for washing. Emulsifiers prevent oils and water from separating.
Polysorbate 20 also adds scent to a product. Since it is made using sorbitol, it has a sweet scent. Sorbitol can also be found in fruits such as apples and peaches.
The lauric acid used to create Polysorbate 20 is often derived from coconuts.
Polysorbate 20 may not be fungal acne safe.
Learn more about Polysorbate 20Sodium Metabisulfite is an antioxidant and is a preservative.
Sodium Sulfite is a preservative. Preservatives help prevent mold and bacteria from growing in cosmetics.
This ingredient has been shown to break the bonds in hair, acting as a natural straightener.
It is commonly used in food. It should be noted sodium sulfite degrades both vitamins B1 and E.
Fun fact: Sulfites are naturally occuring in wine.
Learn more about Sodium SulfiteWater. 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. Stay hydrated!
Learn more about WaterIngredient Ratings
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When to use
Differin Dark Spot Correcting Serum 2% Hydroquinone 14 ingredients
Differin Dark Spot Correcting Serum 4% Niacinamide 23 ingredients
