This medicinal is the dried root tuber of Asparagus cochinchinensis( Lour.)Merr.(Fam. Liliaceae). It is excavated in the autumn and winter, and then washed clean. After removal of its rootlets and caudex, it is fully cooked or steamed in boilig water and then its skin peeled. Then it is washed clean, dried , sliced and utilized in its unprocessed form.
[ Medicinal Properties ]: Sweet, bitter and cold; relate to lung and kidney meridians.
[ Medicial Efficacies ]:Nourish yin and moisten dryness, clear lung and promote fluid production.
[ CLinical Applications ]: 1. Lung yin deficiency syndrome For yin deficiency with dryness-heat in the lung, manifesting as dry cough with decreased sputum, hemoptysis, sore throat and hoarse voice, it is often combined with Maidong; for lung yin deficiency with interior exuberance of dryness-heat, with Maidong, Shashen and Chuanbeimu.
2. Kidney yin deificiency syndrome for vertigo, tinnitus, soreness and pain in the lumbar region and knees, it iscombined with Shudihuang and Gouqizi. For bone-steaming tidal fever due to yin deficiency with effulgent fire, it is combined with Shengdihuang and Maidong. In the case of Xiaoke (Similar to diabetes )due to protracted kidney yin deficiency with internal heat it is usually combined with Shengdihuang and Shanyao. In the treatment of cough with hemoptysis due to deficiency of lung-kidney yin, it is usually combined with Shengdihuang and Xuanshen.
3. Febrile disease with consumption of fluid, anorexia, thirst and constipation due to intestinal dryness To treat anorexia and thirst in febrile disease with consumption of stomach-fluid and damage of both qi and yin, it is combined with Shengdihuang and Renshen. To treat constipation due to intestinal dryness, it should be combined with Shengdihuang and Danggui.
[ Usage and Dosage ]: 6-12g.
[ Precautions ]: It is more sweet, cold and greasy, so it is contraindicated in patients with diarrhea, due to spleen deficiency and interior exuberance of phlegm-dampness.
[ Medicinal Comparison ]: Similarities : Both Maidong and Tiandong have the fuctions of nourishing lung yin, moistening lung dryness, clearing lung heat, nourishing stomach yin, clearing stomach heat, promoting fluid production and moistening the bowels to relieve constipation; therefore, they are both indicated for lung yin deficiency syndrome, stomach yin deficiency syndrome and constipation due to intestinal dryness. Maidong is slightly cold and weaker in clearing fire and nourishing but less greasy, while Tiandog is more bitter and cold and stronger in clearing fire and moistening dryness.
Differenes: Maidong also clears heart to relieve dysphoria, calms the heart to induce tranquilization and is indicated for dysphoria, insomnia, dream-disturbed sleep , amnesia, palpitations and fearful throbbing, due to deficiency of heart yin with effulgent fire.
Tiandong also nourishes kidney yin, reduces deficiency-fire and is indicated for vertigo, tinnitus, soreness and pain in the lumber region and kness, due to kidney yin deficiency and bone-steaming tidal fever, Xiaoke(diabetes)due to yin deficiency with effulgent fire.
天冬为百合科植物天冬Asparagus cochinchinensis(Lour.)Merr.的块根。主产于贵州、四川、广西等地。秋冬二季采挖,洗净,除去茎基和须根,置沸水中煮或蒸至透心,趁热除去外皮,洗净,干燥,切片或段,生用。