This clinical-level serum features highly stable 25% vitamin C to visibly improve uneven tone, radiance, elasticity & firmness without irritation. This lightweight serum is clinically proven to improve uneven tone + discoloration while boosting radiance and brightening dullness. The pro-collagen formula visibly firms and improves elasticity, so you get advanced results—without irritation. 25% Vitamin C + Glutathione Clinical Serum is formulated with a highly stable blend of oil-and-water soluble vitamin C for optimal effectiveness. Glutathione + patented 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. What are benefits of using vitamin c serum? Vitamin C serums noticeably brighten dullness, promote even skin tone, and visibly improve the look of dark spots & discoloration. By neutralizing free radicals, they protect against environmental damage from UV sun exposure and pollution. Vitamin C serums also improve skin firmness and reduce the appearance of fine lines & wrinkles. What are key ingredients in quality vitamin c serums? Quality vitamin C serums, such as the Paula’s Choice 25% Vitamin C + Glutathione Clinical Serum, often combine multiple forms of vitamin C, such as oil-soluble tetrahexyldecyl ascorbate for deep hydration and noticeable brightening, plus stabilized ascorbyl glucoside to promote even tone and reduce the look of dark spots & discoloration. Potent antioxidants like glutathione help enhance protection against free radicals and support a radiant, even-toned complexion. What skin types are vitamin c serums suitable for? Vitamin C face serums are suitable for most skin types—normal, dry, combination, and oily. They help brighten dullness, promote even skin tone, and visibly reduce discoloration & dark spots. Sensitive skin can benefit from lower-strength formulas with skin-soothing ingredients to reduce the risk of irritation. How long does it typically take to see results from using vitamin C serums? Results from vitamin C face serums typically appear in 4–8 weeks with consistent daily use. Brightening, improved tone, and visibly reduced dark spots become noticeable over time. For best results, apply daily and regularly use SPF during the day to protect skin and maintain benefits.