How to use nicotinamide stock solution correctly?

The understanding of the efficacy of nicotinamide, from nutrition, to acne, to sun protection and anti-aging, to anti-wrinkle, anti-yellowing, to barrier repair, and then to in-depth genetic beauty, is pushing forward step by step, and its role is becoming more and more powerful. An ordinary vitamin is endowed with almost omnipotent "myth" ingredient at once, but in any case, the addition amount of this ingredient in other cosmetics has been kept below 5%. Because nicotinamide itself contains irritation, it is necessary to establish tolerance to nicotinamide during use.

When using it for the first time, apply a small amount of emulsion behind the ear and wrist to see if there is any intolerance. If it is determined that it is intolerant, the dosage can be reduced and can be applied to a small area of the face for three to five days. If there are no adverse reactions, the dosage can be increased. If allergies occur during this process, reduce the dosage or use it every other day. After several days of observation, if the allergy is still serious, it is recommended to give up nicotinamide products. It takes about a week to establish tolerance. If intolerance occurs this week, reduce the dosage immediately to avoid skin damage.