Considerations for the use of azelaic acid twice a day
Now I want to discuss the use of azelaic acid twice a day, and there are many things to think about.

Azelaic acid is gradually used in skin care. If you use it twice a day, you need to check the nature of the skin first. Those with delicate skin should be used for the first time or intolerant. If the human body is strong and weak, the skin is also sensitive. For sensitive and weak muscles, apply azelaic acid twice a day suddenly, for fear of redness and itching. Therefore, for such skin, it is recommended to use it in a small area and at a low frequency. When the skin is used, you should increase the frequency to twice a day.

Furthermore, look at the purpose of use. If it is used to treat common acne, twice a day may help the medicinal effect to last, so as to inhibit Propionibacterium acne, reduce the excessive keratinization of the hair follicle mouth, and obtain better results. However, if it is only for daily skin brightening, once a day or enough, overuse it will tire the skin.

And the opportunity to use it is also heavy. For daytime use, it needs to be equipped with sunscreen. Azelaic acid or increases skin sensitivity to light. If there is no sunscreen protection, after sun exposure, the skin is easily injured and causes pigmentation. And when using it at night, it may be more effective to take advantage of skin repair.

The concentration of the product used also needs to be considered. High concentration, although the effect is strong, it is also highly irritating, and twice a day may not be acceptable to all skin; low concentration, relatively mild, or it may take longer to take effect.

In summary, whether azelaic acid is used twice a day or not, it is necessary to carefully observe the skin characteristics, purpose of use, timing of use and product concentration factors, and proceed with caution to achieve the best state of skin care and avoid the risk of skin damage.