Vitamin B complex tablets can be taken for up to three months. Vitamin B complex tablets are comprehensive B vitamins and essential nutrients for the body, used for the prevention and treatment of malnutrition, anorexia, beriberi and pellagra caused by B vitamin deficiency. If there is a vitamin B deficiency, it is usually necessary to supplement for 1-2 months, and after review, if there is no deficiency, you can stop taking it. It is best not to take it for more than three months to avoid affecting the intake of other trace elements. Adverse reactions such as irritability, fatigue, loss of appetite, occasional flushing of the skin, itching, and possible yellow coloration of the urine can occur with high doses. And daily diet, such as soy products, vegetables, etc. are rich in vitamin B. You can also get vitamin B complex from your diet. It is not recommended to take vitamin B complex for a long time, so as not to cause metabolic abnormalities in the body, and it is recommended to use the drug under the guidance of a doctor.