Should I use both TNS Essential Serum and TNS HA5? I have mature skin. Can I use Tretinoin with both these products?

These are great products and work very well together. Essential Serum should be used right after cleansing both morning and night as an all inclusive blend of growth factors, peptides and antioxidants for complete skin rejuvenation. HA5 is a hydrator with five types of HA that when used in the morning maintains moisture levels in the skin throughout the day. Layer this over your Essential Serum in the morning, and follow it with your SPF. At night, the Essential Serum can be followed by a pea size amount of tretinoin or retinol (every other night or every third night is also appropriate depending on the strength and your skins ability to tolerate tretinoin). Best, 

You can without a problem use Tretinoin with both of these Skin medica products. It is important to remember that Tretinoin should only be used at night time, additionally always remember to use sunscreen appropriately. The frequency of Tretinoin application is typically dictated by the strength. Your skin will dictate what you can tolerate. A thought would be to use the TNS and HA5 in the mornings, and Tretinoin at night. However, your dermatologist could best advise you after seeing your skin type. The most ideal site to buy these products from is the Skin Medica website, or a Dermatologist office in your area which carries the line. Best of luck, Dr.Longwill.

If you have generally dry mature skin, it would be absolutely appropriate to use both TNS essential serum and HA5.  Better yet adding a tretinoin in the evening will further improve cell turnover and promote collagen growth.  All three bring something different and effective to your skin care regimen.