Cosrx Advanced The Vitamin C 23 Serum

This serum contains a high concentration of 23% pure Vitamin C (L-Ascorbic Acid).

Yes, it can be used in the morning, but it is essential to follow up with a broad-spectrum sunscreen (SPF 30 or higher) as Vitamin C can increase sun sensitivity.

It is best suited for adults looking to address concerns such as dullness, uneven skin tone, fine lines, and texture. Individuals new to Vitamin C should start slowly due to the high concentration.

It is recommended to store the serum in a cool, dark place, away from direct sunlight and heat. Refrigeration is often advised after opening to maintain stability and prevent oxidation.

It's best to avoid using high concentrations of Vitamin C simultaneously with other strong actives like AHAs, BHAs, or retinoids in the same routine. Alternate application times or use on different days if necessary. It pairs well with hydrating ingredients.

Results can vary depending on individual skin type and concerns. Many users report seeing improvements in brightness and texture within 2-4 weeks of consistent use.

The 'Renewal' typically indicates an updated or improved formulation compared to previous versions, often focusing on enhanced stability, efficacy, or user experience.

This can be a normal initial reaction due to the high Vitamin C concentration. Reduce frequency of use to 2-3 times a week and ensure you are applying it to well-moisturized skin or mix 1-2 drops with your moisturizer. Gradually increase usage as your skin adjusts. Always wear sunscreen during the day.

This indicates potential oxidation, likely due to exposure to air or light. While it may still be safe to use, its potency might be reduced. Ensure proper storage (cool, dark place, possibly refrigerated) and use within the recommended period after opening. If the color change is drastic or accompanied by an off smell, discontinue use.

Apply a smaller amount of serum and gently pat it into the skin. Allow a minute or two for absorption before applying subsequent products like moisturizer. Ensure you are not applying too many layers of other products before the serum.