Long Dan Xie Gan Tang
龙胆泻肝汤 (Long Dan Xie Gan Tang)
Source: Yi Fang Ji Jie (Collected Explanations of Medical Formulas) — Wang Ang (Qing, 1682)
Description
Long Dan Xie Gan Tang (Gentian Drain the Liver Decoction) is the primary formula for draining excess fire and heat-damp from the Liver and Gallbladder channels. It is indicated for two distinct patterns: upward flaring of Liver fire causing head, ear, and eye symptoms; and downward flowing damp-heat along the Liver channel causing urogenital symptoms. The formula powerfully clears without injuring Yin.
Composition
| Herb | Amount | % | Role | Function |
|---|---|---|---|---|
| Huang Qin | 9g | 13.04% | Chen (Deputy) | Clears heat from Liver and upper burner. |
| Ze Xie | 12g | 17.39% | Zuo (Assistant) | Drains dampness from Liver channel through urination. |
| Mu Tong | 9g | 13.04% | Zuo (Assistant) | Drains damp-heat through urination. |
| Che Qian Zi | 9g | 13.04% | Zuo (Assistant) | Clears heat, promotes urination, drains damp-heat. |
| Dang Gui | 9g | 13.04% | Zuo (Assistant) | Nourishes Blood to prevent bitter-cold herbs from injuring Yin. |
| Sheng Di Huang | 9g | 13.04% | Zuo (Assistant) | Cools Blood, nourishes Yin, prevents injury from draining herbs. |
| Chai Hu | 6g | 8.7% | Shi (Envoy) | Guides formula to Liver and Gallbladder channels. |
| Gan Cao | 6g | 8.7% | Shi (Envoy) | Harmonizes all herbs, protects Stomach. |
Total weight: 72g
Preparation
Decoct in water 20–25 minutes. Take cool or at room temperature. Not for long-term use.
Dosage
Decoction: 1 dose/day. Pills: 6g twice daily. Short-term use only — discontinue when condition resolves.
Similar Formulas by composition
Match score combines dosage-weighted composition (cosine, 70%) with shared-herb overlap (Jaccard, 30%).