Fresh orange peel is not suitable for direct use, because fresh orange peel not only stimulates the stomach, but also has pesticides or preservatives attached to the surface of orange peel, and these harmful substances may not be removed by general washing and sun exposure, so it is best not to make tea or soak wine with fresh orange peel. Fresh orange peel is dried in the sun or at low temperature. The longer the orange peel is aged, the better. Generally, it is placed once every other year before use. Dried tangerine peel tastes warm, pungent and bitter; Entering the spleen and lung meridian can adjust the middle energizer, which can treat stomach disharmony, nausea and vomiting. If the stomach is cold and vomits, it can be used with ginger. Pericarpium Citri Tangerinae has the functions of regulating qi, lowering adverse qi, regulating middle energizer, stimulating appetite, eliminating dampness and resolving phlegm. Mainly used for spleen and stomach qi stagnation and dampness resistance, chest and diaphragm fullness, abdominal distension, anorexia, vomiting, unfavorable stool, poor lung qi, cough with excessive phlegm, and can also be used for the treatment of early breast abscess. After years of research, I know that tangerine peel has many pharmacological effects. 1. Effect on digestive system: The volatile oil contained in dried tangerine peel has a slight stimulating effect on gastrointestinal tract, which can promote the secretion of digestive juice and eliminate gas accumulation in intestinal tract, showing the effects of aromatic invigorating stomach, expelling wind and reducing qi. 2. Effects on cardiovascular system: Chenpi decoction and alcohol extract have exciting effects on myocardium, but they will have inhibitory effects when the dose is too large. In addition, it can also cause slight contraction of blood vessels and rapidly raise blood pressure. Pectin in dried tangerine peel can also prevent arteriosclerosis caused by high-fat diet. 3. Effect on respiratory system: The volatile oil contained in dried tangerine peel has irritating and passive expectorant effects, which makes sputum easy to cough up. Chenpi decoction has a weak dilating effect on bronchi. Its alcohol extract has high anti-asthma effect. 4. Effect on genitourinary system: Chenpi decoction can contract renal blood vessels and reduce urine output. 5. Anti-inflammatory effect: Chenpi decoction combined with vitamin C and vitamin K can enhance anti-inflammatory effect.