La Roche-Posay
Vitamin C12 SerumA serum built around Niacinamide, for barrier repair and smoothing.
A serum built around Vitamin C and Vitamin C, for barrier repair and hydration.
Brand price
USD 54.99 · checked 25 Sept 2026 · brand's site
Brand price
USD 44.99 · checked 25 Sept 2026 · brand's site

At a Glance

They come out differently on Oil-free; that row is shaded. Tap any answer to see why.

Key Ingredients

Fatty alcohol1
Waxy fatty alcohols used as emollients and thickeners; unrelated to drying alcohol.

Benefits

Hydrating5
Boosts hydration and relieves dry, tight skin.
Dimethicone, Dipotassium Glycyrrhizate, Glycerin, Propylene Glycol, Tocopherol
Barrier Repair11
Strengthens and restores the skin's natural barrier.
Caprylyl Glycol, Cetearyl Alcohol, Dimethicone, Glycerin, Glycine Soja Oil, Neopentyl Glycol Dicaprate, Niacinamide, Octyldodecanol, Propylene Glycol, Sucrose Tristearate, Tocopherol
Hydrating6
Boosts hydration and relieves dry, tight skin.
Dimethicone, Glycerin, Hydrolyzed Hyaluronic Acid, Propylene Glycol, Sodium Hyaluronate, Tocopherol
Barrier Repair8
Strengthens and restores the skin's natural barrier.
C13-14 Isoparaffin, Caprylyl Glycol, Cyclohexasiloxane, Dimethicone, Glycerin, Pentaerythrityl Tetraethylhexanoate, Propylene Glycol, Tocopherol

Concerns

May Worsen Seborrheic Dermatitis7
May feed the yeast involved in seborrheic dermatitis.
Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Cetearyl Alcohol, Glycine Soja Oil, Hydrogenated Lecithin, Octyldodecanol, Sodium Stearoyl Glutamate, Sucrose Tristearate
May Worsen Keratosis Pilaris3
May clog follicles or strip skin prone to keratosis pilaris.
May Worsen Seborrheic Dermatitis3
May feed the yeast involved in seborrheic dermatitis.
Acetyl Dipeptide-1 Cetyl Ester, Laureth-7, PEG-20 Methyl Glucose Sesquistearate

Ingredients Side-by-side

Emollient
Alcohol Denat. (in both products)
Fragrance
0 / —
- Denatured alcohol
- May Worsen Dryness
- May Worsen Eczema
- May Worsen Irritation
- May Worsen Rosacea
Smoothing
0 / —
- Niacinamide
- Acne Fighting
- Barrier Repair
- Brightening
- Dark Spots
- Even Tone
- Oil Control
- Pore Refining
- Redness Reducing
Hydroxypropyl Tetrahydropyrantriol
Skin Conditioning
Emollient
- Fatty esters (glyceryl stearate, PEG-100 stearate)
- May Worsen Seborrheic Dermatitis
Emollient
2 / 1
- Fatty alcohol
- Fatty alcohols (Malassezia)
- May Trigger Acne
- May Worsen Keratosis Pilaris
- May Worsen Seborrheic Dermatitis
Skin Conditioning
Antioxidant
- Vitamin C
- Vitamin C (L-ascorbic acid)
- Anti-Aging
- Anti-Pollution
- Antioxidant
- Brightening
- Dark Spots
- Even Tone
Alcohol Denat. (in both products)
Fragrance
0 / —
- Denatured alcohol
- May Worsen Dryness
- May Worsen Eczema
- May Worsen Irritation
- May Worsen Rosacea
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Aqua
Solvent
Alcohol Denat.
Antifoaming, Antimicrobial, Astringent, Fragrance, Solvent, Viscosity Controlling
Alcohol Denat. is a drying alcohol.
Learn more about Alcohol Denat. →Dimethicone
Antifoaming, Skin Conditioning, Emollient, Skin Protecting
Dimethicone is a silicone.
Learn more about Dimethicone →Glycerin
Denaturant, Fragrance, Hair Conditioning, Humectant, Oral Care, Perfuming, Humectant, Skin Protecting, Solvent, Viscosity Controlling
Glycerin may be plant, synthetic or animal depending on the supplier.
Learn more about Glycerin →Potassium Hydroxide
Buffering
Potassium Hydroxide is the inorganic base
Learn more about Potassium Hydroxide →Adenosine
Skin Conditioning
6-Amino-9-beta-D-ribofuranosyl-9H-purine
Learn more about Adenosine →Propylene Glycol
Fragrance, Humectant, Humectant, Skin Conditioning, Solvent, Viscosity Controlling
Propylene Glycol is the aliphatic alcohol that conforms generally to the formula
Learn more about Propylene Glycol →Caprylyl Glycol
Deodorant, Hair Conditioning, Skin Conditioning, Emollient
Caprylyl Glycol is the diol that conforms to the formula
Learn more about Caprylyl Glycol →Xanthan Gum
Binding, Emulsion Stabilising, Gel Forming, Skin Conditioning, Cleansing, Emulsifying, Viscosity Controlling
Xanthan gum
Learn more about Xanthan Gum →Tocopherol
Antioxidant, Fragrance, Skin Conditioning, Occlusive
Tocopherol is vitamin E.
Learn more about Tocopherol →
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