Hey Ronia😊
Thanks for your question ✨
COSRX AHA BHA Clarifying Treatment Toner can often be combined with niacinamide, and they can work well together – especially for balancing the skin and working on pores and texture.
However, it’s important to keep in mind that all skin types are different, and the combination can sometimes be too active for more sensitive skin. Therefore, we always recommend doing a patch test on a small area first, and introducing the products carefully, preferably on different evenings at the start.
When it comes to vitamin C, it should be used separately from AHA/BHA toner, here are suggestions for use:
-Vitamin C in the morning (with sun protection)
-AHA/BHA toner in the evening, followed by niacinamide and moisturizing (if the skin tolerates it)
Experiment and see what your skin responds best to, and ease in so it doesn’t become too much for the skin. If you experience sensitivity, back off.
I hope my answer can be helpful and that you have a lovely day🌞