Can Vit C serum and Hyaluronic Acid be used together? If so, which one first, and how often?

Thank you for your question! Maintaining a good skin care regimen helps prevent skin problems in the future. Skin aging is unavoidable but the process can be slowed down with a proper routine . The proper way to apply your products is to layer them from thin to thickest. For example, after cleansing and toning you would apply your (thin) serum and then follow with a (thicker) moisturizer. Vitamin C should be applied first and followed with HA. During the day you should use a broad spectrum sunscreen with SPF 15 or higher. I prefer Total Defense + Repair Broad Spectrum Sunscreen from SkinMedica. At night, my favorite products to use are the TNS Essential Serum followed with HA5, also from SkinMedica. To obtain the best results from your skincare products they should be consistenly used every day. 

Hey there,Use the vitamin C in the morning after washing your face. Vitamin C tends to be very reactive, so you always want to put it on first. You can follow that with Hyaluronic acid in the morning. Remember to use sunblock after that. Vitamin C is an antioxidant and will protect the skin from sun damage and brighten the skin.  At night time, I usually recommend only using the Hyaluronic acid as a moisturizer.Hope this helps!