This is a question I’m frequently asked. You can use CoR products alongside tretinoin in a couple of different ways. This is always a night regimen; choose what works best for you.
1) If you’ve used trentinoin for a while or aren’t particularly sensitive, after washing your face and thoroughly drying with a soft towel, apply your pea-sized tretinoin divided across the areas of your face. Apply Quench, about the length of your index finger-sized bead of product, to your whole face and neck. Follow with 3-10 drops of Shield.
2) If you are new to tretinoin or are typically sensitive to exfoliants, you’ll want to wash your face, dry thoroughly and the WAIT at least 10 minutes before applying tretinoin, etc. Or, and this is my preferred method, wash and then apply Quench directly after then wait 10 minutes before applying tretinoin. Follow immediately with 3-10 drops of Shield. I like this method because it buffers the medication even more than the other protocols.
Just as a reminder: if you’re using Quench in the morning after cleansing, you want to use it on damp skin as opposed to the tretinoin evening regimen where the skin needs to be dry to avoid irritation.