Fructus Aurantii Immaturus and Fructus Aurantii Immaturus are the same thing, the big one is the shell (that is, the fruit without pulp is close to maturity), and the small one is real (that is, the immature fruit). Both of them are slightly cold, bitter and pungent, and both of them can invigorate qi, promote digestion, eliminate accumulation, resolve phlegm and remove swelling. It can be used for treating dyspepsia, flatulence, constipation, diarrhea, acute diarrhea, fullness of chest and diaphragm, flatulence, gastroptosis, rectocele, and yin rigidity caused by phlegm-dampness stagnation. In recent years, it has been found that both of them can be made into injections and administered intravenously, which have the effect of raising blood pressure. The difference is that Fructus Aurantii Immaturus has a strong effect, which can break qi and eliminate food stagnation and is used for defecation. Fructus Aurantii has slow action, regulates qi and is lenient, and is used to eliminate fullness.