Hi Niina and thank you for your question! 💛
The product contains 20% acids (AHA + PHA) and has a fairly low pH, so we do not recommend using it the same evening as retinal. Both acids and retinal speed up cell renewal, and when used together, they can increase irritation, dryness, and sensitivity.
The best way to combine them is to use them on different evenings – for example, acids 1-3 times a week and retinal on the other evenings, depending on your skin's tolerance. Also remember daily sun protection, as both acids and retinal make the skin more sensitive to the sun ☀️
If you tell us how often you use retinal and what your skin type is, we would be happy to help you build a suitable routine! 💕