20% THD Ascorbate
Tetrahexyldecyl Ascorbate is a lipid-soluble, highly stable form of vitamin C selected for rapid absorption, visible brightening and antioxidant support without relying on a water-based L-ascorbic acid system.
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Fast-absorbing vitamin C serum protects from sun and pollution while enhancing firmness and brightness for all skin types.
C Antioxidant Gel 20% delivers 20% Tetrahexyldecyl Ascorbate (THD Ascorbate), a lipid-soluble and highly stable form of vitamin C, in a lightweight water-free base. Paired with Vitamin E, the formula provides daily antioxidant support while helping improve the look of firmness, uneven tone, discoloration and diminished radiance.
A Dr. Alster Pick, C Antioxidant Gel 20% combines 20% THD Ascorbate with a water-free gel base, Vitamin E antioxidant support and airless packaging designed to help preserve formula stability.
Its light, non-greasy texture absorbs quickly and layers cleanly under moisturizer and SPF, making high-strength antioxidant support easy to integrate into a daily regimen and appropriate for professionally directed post-treatment protocols.
Tetrahexyldecyl Ascorbate is a lipid-soluble, highly stable form of vitamin C selected for rapid absorption, visible brightening and antioxidant support without relying on a water-based L-ascorbic acid system.
Tocopherol Acetate provides complementary antioxidant support and reinforces the formula's focus on defending skin from oxidative stress associated with environmental exposure.
The anhydrous gel base is designed to absorb quickly and resist the oxidation concerns associated with many water-based vitamin C formulas, while the airless package helps preserve product potency.
Use morning and evening on freshly cleansed, dry skin. Allow the gel to absorb fully before applying moisturizer, sunscreen or makeup. Mild tingling may occur when first introducing this high-concentration vitamin C formula.
Apply a thin layer to freshly cleansed, dry skin on the face, neck and décolleté in the morning and at night. Allow the product to absorb before layering moisturizer, sunscreen or makeup.
C Antioxidant Gel 20% can be incorporated into post-treatment and device-enhanced skin-renewal protocols when directed by a treating professional. Follow procedure-specific timing and aftercare instructions before resuming active skincare.
Cyclopentasiloxane, Isododecane, Polysilicone-23, Tetrahexyldecyl Ascorbate, Tocopherol Acetate.
Apply to face, neck, and décolleté twice daily.
Visible signs of aging — fine lines, loss of elasticity, diminished radiance and early collagen decline.
Skin discoloration and uneven tone — sun-spots, post-treatment hyperpigmentation, dullness and pigmentation drift.
Environmental & sun-related damage — oxidative stress from UV, HEV/blue light, pollution and post-procedure skin recovery.
AM | PM • All Skin Types
• Water-free formulation ensures product stability, efficacy, and shelf-life
• Provides antioxidant defense against skin damage associated with free radicals
• Helps brighten tone and reduce the occurrence of skin discoloration caused by sun exposure
• Lightweight texture absorbs quickly and layers well with other products
• Formulated with lipid-soluble vitamin C for rapid, deeper absorption
Cyclopentasiloxane, Isododecane, Polysilicone-23, Tetrahexyldecyl Ascorbate, Tocopherol Acetate.
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Protect, brighten, and nourish your skin with The A Method’s C Antioxidant Gel 20%.
Formulated with a 20% concentration of THD-ascorbate—a fat-soluble, highly stable form of vitamin C—this lightweight antioxidant vitamin C gel helps defend against sun damage, minimize dark spots, and visibly improve firmness and tone.
Gentle, fast-absorbing, and fragrance-free, it’s ideal for all skin types, including sensitive and oily skin.
With consistent use, it can help minimize visible signs of aging by reducing the appearance of fine lines, age spots, and sun-related discoloration.
Allow the serum to absorb fully before layering other skin care products like moisturizer or sunscreen. A mild tingling sensation may occur at first, which is normal when introducing a high-concentration vitamin C product.
The key ingredients include:
Together, these ingredients deliver antioxidant properties that help support overall skin health and maintain an even skin tone.
Formulated to respect even the most sensitive skin, this product delivers visible antioxidant benefits without unnecessary additives or irritants that could contribute to redness.
When using other active ingredients like salicylic acid, ascorbyl glucoside, or all-trans retinol, introduce them gradually to avoid overloading the skin. Pairing it with a broad-spectrum SPF during the day is especially important for maximum protection.
Note: Topical vitamin C complements your overall skincare routine, but it works on the surface of the skin. It does not replace the benefits of dietary supplements or a healthy diet rich in vitamin C.
While a topical vitamin C serum helps protect and nourish the skin’s surface, it cannot correct systemic deficiencies in the body. If you are concerned about symptoms of vitamin C deficiency, it’s important to talk to your doctor. They can recommend the right approach based on your overall health needs.
Still have questions? Email our support team at info@theamethod.com or fill out this contact form. We typically reply within 24–48 hours.I am a woman in my 70's with very fair skin and a lot of sun damage from growing up in Southern California. I have been using A Method 20% C Gel for several years now. I love it. It is smooth and easy to apply and does not irritate my skin. As part of a low dose retinol/C program it has done a lot to reduce redness and spotting on my face and chest.
I’m a repeat customer and I have gotten this for friends and family as well. I have never seen a skincare product work as well as this. The new packaging is also effective at preserving the serum. This is better than any other Vitamin C on the market in my opinion.
At first I thought that 20% vitamin C might be too strong, but it isn’t. I love that it’s so light-weight and spreads so easily over the face. This Vitamin C serum is a must!
I use many of the A Method products; however, if I had to choose to pick one to rave about it would be C Antioxidant Gel 20%. My skin feels so smooth after applying. I was attracted to this skin care line because it is 100% "medicinal grade." This means that the ingredients actually work to repair damaged skin and you WILL SEE RESULTS! Start using the entire system and gain your "own" personal testimony.
It's easy to apply and not-sticky.