Can I use niadynamide every morning, glycolic acid on Tuesdays, Thursdays and Saturdays in the evening, and azelaic acid in the evening?

It is difficult to propose a specific way of care only on the basis of such a short description. Before taking any skin care, I encourage you to consult a dermatologist or beautician. The right specialist will be able to assess the condition of your skin and adjust the appropriate products according to her individual needs of your skin. If you are not able to take advantage of the advice, I enclose a link to the online teleadvice, e.g. via the Gdziepolek.pl portal: https://www.gdziepolek.pl/telekonsultacja If the specialist accepts this care plan, it is important to follow the recommendations regarding the dosage and frequency of use of each product. Here are some considerations to consider: Niacinamide: This is a fairly mild ingredient that can usually be used every morning. Nevertheless, if you have sensitive skin, it is worth starting by applying it every other day and observing the reaction of your skin. e.g. La Roche-Posay Pure Niacinamide 10: https://www.gdziepolek.pl/produkty/118043/la-roche-posay-pure-niacinamide-10-serum-do-twarzy-plyn/apteki Glycolic acid: This is a stronger acid that helps in exfoliating the skin. Using it three times a week (Tuesdays, Thursdays and Saturdays) may be appropriate, but it is important to avoid excessive skin irritation. To begin with, it is worth starting with a lower concentration and gradually increasing if your skin allows it. e.g. LIQ CG Serum Night Glycolic Peel: https://www.gdziepolek.pl/produkty/95724/liq-cg-serum-night-glycolic-peel-plyn/apteki Azelaic acid: This is a fairly delicate acid that helps fight acne and hyperpigmentation. Its use for the remaining days in the evening is reasonable, but also here it is worth starting with fewer days and observing the reaction of the skin. e.g. Skinoren: https://www.gdziepolek.pl/produkty/71823/skinoren-krem/apteki Also, do not remember to use well-chosen moisturizers and sunscreens during the day, as the active ingredients can make the skin more susceptible to sun damage.