25% Vitamin C + Glutathione Clinical Serum

25% Vitamin C + Glutathione Clinical Serum is formulated with a highly stable blend of oil-and-water soluble vitamin C for optimal effectiveness. Glutathione + GAP technology (glutathione amino acid precursors) work to minimize irritation while amping up antioxidant protection and ingredient stability. This clinical-level formula helps sustain a natural level of glutathione & vitamin C within skin’s most uppermost layers for extended results, while reducing oxidative stress that triggers discoloration.

This lightweight vitamin C serum is clinically proven to improve uneven tone + discoloration while boosting radiance and brightening dullness. The pro-collagen formula visibly firms and improves the look of elasticity so you get advanced results—without irritation.

Apply onto face and neck. For optimal results, use AM and PM. For daytime, follow with SPF 30+.

Key Ingredients: Tetrahexyldecyl Ascorbate, Ascorbyl Glucoside, Glutathione, Pyrus Malus (Apple) Fruit Extract, Ergothioneine

All Ingredients: Aqua/Water/Eau (Solvent | Good), Tetrahexyldecyl Ascorbate (Antioxidant | Best), Dimethicone (Silicone, Emollient | Best), Glycerin (Humectant, Texture Enhancer, Solvent | Best), C9-12 Alkane (Solvent | Good), Ascorbyl Glucoside (Antioxidant | Best), Silica (Texture Enhancer, Absorbent, Occlusive/Opacifying Agent | Good), Pyrus Malus (Apple) Fruit Extract (Antioxidant, Plant Extracts, Humectant | Best), Hydrogenated Lecithin (Emollient, Emulsifier, Suspending/Dispersing Agent | Best), Polyglyceryl-6 Polyricinoleate (Emollient, Emulsifier, Texture Enhancer | Good), Acrylates/C10-30 Alkyl Acrylate Crosspolymer (Texture Enhancer, pH Adjuster/Stabilizer, Polymer | Good), Xanthan Gum (Texture Enhancer, Cleansing Agent, Emulsifier | Good), Oryza Sativa (Rice) Bran Extract (Humectant, Antioxidant, Chelating Agent | Best), Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer (Suspending/Dispersing Agent, Texture Enhancer, Polymer | Good), Cetyl Alcohol (Texture Enhancer, Emollient, Emulsifier | Good), Caprylyl Glycol (Preservative, Plant Extracts | Good), Lysine Carboxymethyl Cysteinate (Antioxidant | Best), Coco-Caprylate/Caprate (Emollient | Good), Tocopherol (Antioxidant | Best), Glutathione (Antioxidant | Best), Sodium Citrate (pH Adjuster/Stabilizer, Chelating Agent, Antioxidant, Preservative | Good), Sodium Phytate (Chelating Agent | Good), Hexylene Glycol (Solvent, Texture Enhancer | Good), Ethylhexylglycerin (Preservative, Humectant | Good), Helianthus Annuus Sunflower Seed Extract (Antioxidant, Plant Extracts | Best), Urea (Humectant, Exfoliant, pH Adjuster/Stabilizer | Best), Mannitol (Humectant | Good), Caprylic/Capric Triglyceride (Emollient, Texture Enhancer, Plant Extracts | Best), Sodium PCA (Humectant | Best), Rosmarinus Officinalis (Rosemary) Leaf Extract (Plant Extracts, Antioxidant | Good), Polysorbate 60 (Cleansing Agent, Emulsifier | Good), Sorbitan Isostearate (Cleansing Agent, Emulsifier | Good), Trehalose (Humectant | Good), Ascorbic Acid (Antioxidant, pH Adjuster/Stabilizer | Best), Glucose (Humectant, Prebiotic/Probiotic/Postbiotic | Good), Vanilla Planifolia Fruit Extract (Plant Extracts, Antioxidant, Fragrance: Synthetic and Natural | Good), Polyquaternium-51 (Film-Forming Agent, Humectant | Good), Ergothioneine (Antioxidant | Best), Triacetin (Solvent, Texture Enhancer, Preservative | Good), Sodium Hyaluronate (Humectant, Antioxidant | Best), Phenoxyethanol (Preservative | Good)

Ingredient Spotlight:

• Tetrahexyldecyl Ascorbate: Highly stable form of vitamin C that protects skin from oxidative damage and collagen breakdown. Oil-soluble, more stable form of vitamin C; Can help preserve’s skin collagen; Antioxidant helps fight damaging free radicals
• Ascorbyl Glucoside: Stable, water-soluble form of vitamin C that brightens dull skin and fades discolorations. Stable form of vitamin C easily penetrates skin; Brightening benefits enhanced by niacinamide; Helps improve skin’s environmental defenses
• Glutathione: This ingredient, which occurs naturally in skin, has potent antioxidant benefits and serves as a skin-restoring, dullness brightening ingredient in topical products. Occurs naturally in skin; Defends against environmental damage; Offers restoring and tone-improving benefits
• Pyrus Malus (Apple) Fruit Extract: This fruit extract is a rich source of free radical-scavenging antioxidants and has hydrating properties. Rich source of polyphenolic antioxidants; Scavenges free radicals before they damage skin; Improves skin’s hydration
• Ergothioneine: Potent, mushroom-derived antioxidant that boosts skin’s environmental defenses and ability to look younger in multiple ways. Helps skin look younger in multiple ways; Helps fade signs of discoloration; Offers soothing benefits

Journal of Clinical and Aesthetic Dermatology,October 2023, pages 31-38
Experimental Gerontology, December 2022, pages 1–11
Antioxidants, August 2022, pages 1–18
International Journal of Cosmetic Science, December 2021, pages 691-702
Journal of Cosmetic Dermatology, September 2021, pages 2,349–2,359
Journal of Cosmetic Dermatology, December 2020, pages 3,251-3,257
International Journal of Cosmetic Science, August 2019, pages 378-386
Clinical Cosmetic and Investigative Dermatology, April 2017, pages 147-153; and October 2014, pages 267-274

Who should use 25% Vitamin C + Glutathione Clinical Serum?

The 25% Vitamin C + Glutathione Clinical Serum is for all skin types, skin tones and ages. It is best for those showing numerous, more stubborn signs of sun damage, including dark discolorations, a dull complexion and moderate loss of firmness.

What is the difference between 25% Vitamin C + Glutathione Clinical Serum and C15 Super Booster?

The 25% Vitamin C + Glutathione Clinical Serum contains two vitamin C esters: 23% tetrahexyldecyl and ascorbate and 2% ascorbyl glucoside and is best suited for those with advanced concerns of discolorations, uneven skin tone and lack of firmness. TheC15 Super Boostercontains 15% pure ascorbic acid (vitamin C) and is a great option for everyone who wants a daily dose of vitamin C to help fortify skin and improve minor skin discolorations or dullness. It can be used alone or mixed into your favorite serum or non-SPF moisturizer.

Each product can be used on its own or in combination with one another (e.g., C15 during the day and 25% Vitamin C at night). Whether to use one or both will depend on your primary concerns and tolerance for these ingredients. We suggest experimenting to see what works best for your skin. As with all bioactive ingredients, start slowly and increase use as desired/needed.

Note: You may notice ascorbic acid listed at the bottom of the ingredient list for this product. The ascorbic acid is present in this formula in incidental amounts. As such, it does not have a brightening or antioxidant benefit to the skin. Instead, it's part of the ascorbyl glucoside blend, used to help keep it stable and in the ideal pH range prior to being added to a cosmetic formula.

What is the difference between 25% Vitamin C + Glutathione Clinical Serum and the C25 Super Booster?

The 25% Vitamin C + Glutathione Clinical Serum is a comprehensive formula made for all-over facial use. With 23% tetrahexyldecyl ascorbate and 2% ascorbyl glucoside, it’s the most potent vitamin C product we offer and a great option for targeting stubborn concerns such as discolorations, uneven skin tone, fine lines and wrinkles.

The formula is water-based and contains several supporting ingredients, including potent antioxidants glutathione and ergothioneine. It also includes GAP technology, an amino acid blend proven to boost skin’s glutathione levels for enhanced activity of vitamin C and improved pollution defense (which helps further minimize the intensity of dark circles). While the C25 Super Booster was a great product, it was a spot treatment with a less robust formula that relied on 25% l-ascorbic acid to help fade discolorations.

What is the difference between 25% Vitamin C + Glutathione Clinical Serum and CLINICAL Discoloration Repair Serum?

The 25% Vitamin C + Glutathione Clinical Serum contains 23% tetrahexyldecyl ascorbate and 2% ascorbyl glucoside, plus glutathione, GAP Technology and ergothioneine. This serum is great for targeting uneven tone, discolorations and loss of firmness. TheCLINICAL Discoloration Repair Serumcontains 3% tranexamic acid, 5% niacinamide and 0.5% bakuchiol which is ideal for targeting discolorations and is even suitable for those with melasma-prone skin . It is also soothing, which can reduce signs of redness. It is perfectly fine—and in some cases may be advisable—to layer both products as part of your strategy to fade various types of hyperpigmentation, including post-breakout marks.

Where should I store 25% Vitamin C + Glutathione Clinical Serum?

While there is research that supports it’s okay to keep water-based ascorbic acid (pure vitamin C) in the refrigerator to help prolong stability and delay in color change, it’s important to note that this only applies to ascorbic acid in water. This does not apply to other ingredients or forms of vitamin C or when ascorbic acid is present without water. The only vitamin C product in the Paula’s Choice line we say is okay to store in the refrigerator is our C15 Super Booster, but even then, such storage is optional; room temperature is ideal. For other products, long-term exposure to cold temperatures can shorten the product’s lifespan, negatively impact stability and affect performance. The 25% Vitamin C + Glutathione Clinical Serum was deemed best stored at room temperature which is typically 68–72F (20– 22C). Refrigerating it to preserve the incidental amount of ascorbic acid would have a net negative effect on many of the other ingredients not meant for long-term cold storage. Note: The PAO (period after opening) for the 25% Vitamin C + Glutathione Clinical Serum is 12 months. For more information aboutrefrigerating skin care productsand our products’ shelf life, please visit ourHelp Center.

Can you mix 25% Vitamin C + Glutathione Clinical Serum with C15 Super Booster or layer under C5 Super Boost Moisturizer?

Yes. In fact, you will see enhanced results and not have to worry about irritation since the forms of vitamin C in the 25% Vitamin C + Glutathione Clinical Serum do not have the same low pH requirements as pure ascorbic acid. You will get better free radical protection, better environmental defense and enhanced improvements in discolorations, wrinkles and loss of firmness. We recommend starting slow with multiple bioactive products to see how your skin responds and increasing use over time as needed/desired.

Can you mix 25% Vitamin C + Glutathione Clinical Serum with other bio-active products?

Yes, research has shown that vitamin C works well and can be used with other beneficial ingredients including niacinamide, retinol, peptides (except copper peptides, which Paula’s Choice does not use) and exfoliating acids. If you are currently using a prescription skincare product, we recommend consulting with your doctor for guidance on incorporating this serum into your routine. Here’s a few of our favorite combos: Vitamin C + Retinol: Retinol (in the form of retinyl palmitate) and vitamin C (ascorbic acid) are naturally present in skin, where they work to keep it healthy.Vitamin C and retinolcan coexist and maintain their benefits in a single formula, or they may be formulated separately and layered. Vitamin C + Peptides: Vitamin C plays well with almost allpeptides,working to protect skin and helping it repair damage. The only exception: copper peptides. These can oxidize vitamin C, making it less effective on skin. When using vitamin C and copper peptides in your routine, we recommend using one in the morning and the other at night to ensure maximum effectiveness. Vitamin C + Niacinamide: Together,vitamin C and niacinamideform a powerhouse combo that addresses uneven tone, wrinkles, loss of firmness and dullness. All skin types will see a complexion that becomes more radiant, smoother, more even and younger-looking when pairing the two ingredients. Vitamin C + AHA/BHA: The exfoliating action ofAHA or BHAhelps shed the buildup of skin cells that in turn allow vitamin C to penetrate past the skin’s surface. Using AHA/BHA prior to applying vitamin C enables it to be more effective.

Is 25% Vitamin C + Glutathione Clinical Serum good for breakout-prone skin?

Yes, when used with ourCLEAR anti-acne collection, the soothingbenefits of vitamin Cand key antioxidants in this serum can help to reduce some of the inflammation that drives acne. These ingredients can also help to fade post-breakout marks of any color.

Is 25% Vitamin C + Glutathione Clinical Serum good for rosacea or sensitive skin?

This may vary from person to person due to the amount of vitamin C in the formula which may prove too potent. We suggest patch testing this product on a small area to see how your skin responds. Vitamin C's soothing action on the skin can be helpful for rosacea, as can the anti-rednessbenefits of glutathioneand ergothioneine. If you've experienced sensitization to higher amounts of vitamin C, we recommend you consider ourC5 Super Booster Moisturizerwhich contains 5% vitamin C.

Is it safe to use 25% Vitamin C + Glutathione Clinical Serum during pregnancy or while breastfeeding?

The ingredients in the 25% Vitamin C + Glutathione Clinical Serum are generally considered safe to use during pregnancy or while breastfeeding. However, if you’re uncertain about starting a new anti-aging product or a combination of ingredients, check with your physician and follow their advice. For additional information on the topic, be sure to review the following article:Which Skin Care Products Are Safe During Pregnancy?

How often should you apply 25% Vitamin C + Glutathione Clinical Serum?

The 25% Vitamin C + Glutathione Clinical Serum can be applied up to twice per day, in your AM and PM routine. How often to apply will vary based on your concerns and tolerance. If new to using vitamin C or higher concentrations of the ingredient, start slow (2-3 times per week), see how your skin responds, and then work up to increasing to daily use.

How do you apply 25% Vitamin C + Glutathione Clinical Serum?

Smooth a dime sized amount over face and neck. For optimal results, use AM and PM. For daytime, follow with a broad-spectrum sunscreen rated SPF 30 or greater.

We recommend layering the products in your routine from thinnest to thickest texture. You can also cocktail the products together by simply mixing the appropriate amount of each in your hand, combining, and applying in a single step.

Can I use vitamin C with retinol?

Yes, vitamin C and retinol complement each other in an anti-aging routine. For best results, use vitamin C in the morning for antioxidant support throughout the day, and apply retinol at night. If you prefer to use both at night, apply vitamin C first, let it absorb and then follow with retinol.

What does glutathione do in this serum?

Glutathione is a potent antioxidant that helps support skin’s natural antioxidant defenses and works alongside vitamin C to visibly brighten and help improve the look of dark spots. Combined with our GAP Technology (glutathione amino acid precursors), it’s designed to help boost antioxidant support while minimizing irritation and helping maintain formula stability.

Can I use this vitamin C serum with niacinamide?

Yes, vitamin C and niacinamide can be used together. Research shows they work well in the same routine and can complement each other’s brightening benefits. Apply the 25% Vitamin C + Glutathione Clinical Serum first, let it absorb, then follow with niacinamide products.

Does this vitamin C serum work well under makeup?

Our lightweight vitamin C serum layers well under makeup. A thin layer, allow it to absorb, then follow with moisturizer and/or sunscreen before foundation, skin tints, or other complexion products.