Vitamin B1 can be taken for at least a month before it takes effect, enabling the deficiency to be effectively replenished, leading to an improvement in symptoms. Vitamin B1 is a water-soluble vitamin, the main effect can be to promote digestion, the improvement of mental state can have a certain role. It also plays a role in maintaining the stability of the heart, muscles, and nervous tissue activity. In addition, for foot fungus disease or shingles disease treatment can also have a certain auxiliary effect. Because of these effects, vitamin B1 is currently used in the treatment of neurasthenia, cardiac neurosis and other diseases. Vitamin B1 as a drug, need to be taken under the guidance of a doctor. If the symptoms are not relieved after a month of continuous use, you need to stop using vitamin B1. Since vitamin B1 can not be used for a long time, to prevent nausea, diarrhea, dizziness and other uncomfortable symptoms.