Timeless Vitamin C + E + Ferulic Acid Serum — 20%, 1 oz

The L-Ascorbic Acid + Vitamin E + Ferulic Acid combination is the most evidence-backed antioxidant trio in published skin science. A 2005 dermatology study showed the combination is approximately 8x more photoprotective than vitamin C alone and significantly more stable than single-ingredient formulas. It's the same active formula that SkinCeuticals CE Ferulic built its reputation on at $185 per oz.11 ingredients. Fragrance-free.

Before you buy — what you need to know.

This formula uses L-Ascorbic Acid, the most studied but most demanding form of vitamin C. It requires a low pH (~2.5-3.5) to penetrate and work — which means it can sting or tingle, especially when you first start using it. Sensitive, dry, or reactive skin may need a slower introduction or may prefer the Ursa Major Vitamin C Serum instead (stable vitamin C derivatives, no pH requirement, no tingling). Also: refrigerate this serum and use within 6 months. Unrefrigerated, L-Ascorbic Acid oxidizes and the formula turns orange — the visual signal that it's losing potency. The effectiveness at month one, stored correctly, is dramatically better than a half-gone bottle that sat on a shelf all summer.

Why people use it

• Delivers the maximum clinically-studied brightening effect from the vitamin C + E + ferulic acid triple combination
• Fades the appearance of dark spots and hyperpigmentation with consistent daily use over weeks
• Antioxidant protection against the daily environmental stressors that cause cumulative skin tone unevenness
• Works with sunscreen in the morning — the antioxidant layer beneath SPF adds photoprotection that sunscreen alone doesn't provide
• One of the best value-per-effective-dose vitamin C serums available: same active chemistry as serums that cost 4-7x more

What's inside

• L-Ascorbic Acid (20%) — the most-studied topical vitamin C form; at 20% concentration in the correct pH environment, the most evidence-backed vitamin C dose for brightening and antioxidant protection. Works only in L-Ascorbic Acid form — ascorbic acid derivatives convert to this on skin at lower efficiency
• Alpha-Tocopherol (Vitamin E) — a complementary antioxidant that, combined with Vitamin C, creates a synergistic effect: each regenerates the other, extending antioxidant activity significantly beyond either alone
• Ferulic Acid — a plant-derived antioxidant (from the cell walls of rice, wheat, oats) that stabilizes both Vitamin C and Vitamin E in the formula and multiplies their combined photoprotective effect
• Ethoxydiglycol — a skin-penetration enhancer that delivers the L-Ascorbic Acid through the skin's barrier at the acidic pH required for efficacy; the same carrier used in the SkinCeuticals formula it mirrors
• Sodium Hyaluronate — surface hydration that counterbalances the low pH and helps the formula feel comfortable after absorption
• Panthenol (Vitamin B5) — a soothing humectant that helps reduce post-application dryness

Good to know

• 1 fl oz glass bottle with pump
• Apply 1-2 pumps to freshly cleansed face and neck in the morning; let fully absorb before moisturizer; always follow with SPF
• Refrigerate after opening and use within 6 months — L-Ascorbic Acid oxidizes; a yellow-to-orange color change indicates degradation and reduced efficacy. A fresh bottle is pale yellow; discard once significantly orange.
• At 20% L-Ascorbic Acid and pH ~2.5-3.5, this serum can cause tingling and mild irritation when first introduced — start every other day and build to daily use. If you experience persistent irritation, switch to the Ursa Major Vitamin C Serum (stable vitamin C derivatives, no low pH)
• The formula has a characteristic metallic/tangy smell on application from the L-Ascorbic Acid — this is normal and fades after it absorbs
• Contains Propylene Glycol (penetration enhancer) — relevant for customers who avoid it on clean beauty ingredient lists
• Fragrance-free, paraben-free, dye-free, cruelty-free, vegan, Made in USA

Full ingredient list Water (Aqua/Eau), Ethoxydiglycol, L-Ascorbic Acid (20%), Propylene Glycol, Alpha Tocopherol (Vitamin E), Polysorbate 80, Panthenol (Vitamin B5), Ferulic Acid, Sodium Hyaluronate, Benzyl Alcohol, Dehydroacetic Acid