Astringent Chinese Medicinal Herbs
Chinese medicinal herbs with the main actions of inducing astringency and arresting discharge are called astringents.

This kind of Chinese medicinal herbs are mostly sour and astringent in flavor, respectively having the actions of stopping the excessive perspiration, relieving diarrhea, and nocturnal emission, reducing urination, stopping leucorrhea, bleeding, and cough, etc. Therefore, they are indicated for abnormal leakage of body substances due to weakness and unconsolidation of healthy essence manifested as spontaneous sweating, night sweating, chronic diarrhea and dysentery, spermatorrhea, seminal emission, frequent micturition, chronic recurring cough and dyspnea, leucorrhea and others.

The purpose of using astringents is to induce astringency to prevent decline of anti-pathogenic factors and appearance of complications caused by involuntary discharge. But the principal cause of abnormal discharging of body substances is due to the deficiency of healthy qi, so astringents should be used in combination with appropriate tonics to treat both the principal and secondary aspects of diseases. For example, in treating spontaneous sweating due to deficiency of qi, or night sweating due to deficiency of yin, they should be used respectively in combination with qi invigorating tonics and yin nourishing tonics; in treating chronic diarrhea, dysentery and leucorrhea due to asthenia of the spleen and kidney, they should be used in combination with the spleen and kidney benefiting tonics; in treating spermatorrhea, seminal emission, enuresis, frequent urination due to kidney deficiency, they should be used in combination with kidney tonifying medicinal herbs; in treating unconsolidation of thoroughfare and conception vessels, metrorrhagia, they should be used in combination with Chinese medicinal herbs that consolidate thoroughfare and conception vessels; in treating lung and kidney diseases due to asthenia of viscera, chronic cough with dyspnea resulting from asthenia, they should be used in combination with medicinal herbs that improve inspiration by invigorating lung and kidney qi.

Astringents have a "closing" effect on the body to prevent further discharge from the body, therefore, they are not suitable in the case with exogenous pathogenic factors that are not removed or interior stagnation of any dampness and domination of sthenia pathogenic factors.