If you want to know whether azelaic acid and nicotinamide can be used together, you need to investigate the properties of the two in detail. Azelaic acid has antibacterial and anti-inflammatory effects, and can improve abnormal keratinization. It is often applied to acne, rosacea and other diseases. Niacinamide can regulate sebum secretion, increase skin barrier, lighten pigmentation, and brighten skin tone. It is commonly used in skin care.

From a pharmacological point of view, there is no danger that the two will be mutually exclusive. Azelaic acid is acidic, and the properties of nicotinamide are relatively stable. The two are compatible, and they will not cause chemical reactions and reduce effect or harm. There are also many clinical examples. I see that the two are used together to improve acne and skin dullness, which can complement each other.

However, there are individual skin conditions, or there are people who are sensitive to either. Therefore, when using it for the first time, it is advisable to try it on a small scale to check the skin's response. If you see redness, swelling, itching and other discomfort, stop using it immediately and consult a doctor. In short, azelaic acid and nicotinamide can usually be used together. When using it, you must pay careful attention to the state of the skin to ensure the safety and effect of skin care.