Thymopentin injection is an immune booster, mainly used for the following diseases: i. It is used for patients with chronic hepatitis B who are over 18 years old. Because thymus gland starts to atrophy and cellular immune function decreases after 18 years old. II. For various primary and secondary T-cell deficiency diseases, such as childhood congenital immunodeficiency disease. Third, for certain autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, etc. Fourth, it is used for various diseases with low cellular immune function. V. Thymopentin is an adjuvant drug for tumor treatment. The tolerability of thymopentin is relatively good, individual can have adverse reactions such as nausea, dizziness, chest tightness, weakness, etc. A few patients occasionally have drowsiness.