Taking niacinamide orally does not necessarily lead to whitening. On the contrary, if niacinamide is abused in large amounts or for a long time, it may cause unwanted side effects and even poisoning. Niacinamide is mainly used clinically for dermatitis formed by niacin deficiency, such as pellagra or tongue inflammation and dermatitis due to niacin deficiency. Generally after treatment with this drug, the roughness of the skin may be improved and the inflammation of the skin may also be improved. In addition, along with oral medication, sometimes it is also necessary to take oral B vitamins, such as vitamin B1, vitamin B2 or directly oral vitamin B complex. However, it can not be used in large quantities for a long time, this drug and the patient’s whitening, there is no direct effect, you can not blindly use the drug.