This is such a great Vit. C serum, I do recommend storing it in your fridge and not exposing it to light (as much as you can help it) to make it last longer. I can use one bottle for 3 months before it starts going bad and I need to restock. The results a well worth it though, has really helped exfoliate and heal my skin. I also have a lot of redness it has helped even out. I have combination, acne prone/slightly sensitive skin.