This formula is for concurrent deficiency of qi and yin, primarily of the Lungs. Chronic cough not only injures the Lung qi, but is also an manifestation of injured Lung qi together with shortness of breath and spontaneous sweating. Prolonged, profuse sweating injures the fluids and yin, which is manifested here in the sparse sputum that is difficult to expectorate, and the dry mouth and tongue. The pulse is deficient, which reflects deficient yin. The same condition can develop over a relatively short period of time if the sweating is profuse, as in summerheat-stroke or heat-stroke. The mechanism in such cases is that excessive sweating injures both the Lung qi and the fluids or yin. When qi deficiency develops quickly, it almost always products a tendency to curl up. The author of this formula, Li Ao, designed it for heat injuring the basal or source qi. Later generations of physicians expanded its scope. Recently this formula has been widely used in treating various types of heart disease, including palpitations and coronary artery disease. It is particularly useful in treating palpitations with a stifling sensation in the chest, shortness of breath, sweating, a dry mouth and thirst, poor sleep, a pale, red, and dry tongue, and a slow-irregular or consistently-irregular pulse. When this formula is used in treating a critical condition, no substitution should be made for Radix Ginseng (Ren Shen). It is interesting no note that under the entry for this herb in the Divine Husbandman's Classic of the Materia Medica, it is said to "tonify the five yin organs, calm the essential spirit, steady the souls, and relieve palpitations with anxiety." All of these functions are drawn upon this this formula. However, for debility following a febrile disease, Radix Panacis Quinquefolii (xi yang shen), which tonifies both the qi and the yin, if preferred. This is one of the few formulas that are used in treating acute collapse.* --Bensky: Chinese Herbal Medicine Formulas and Strategies.