Eucommia Bark — Classic Formulas

Du Zhong · Cortex Eucommiae

Primary Actions

  • Tonifies the Liver and Kidney and strengthens tendons, bones, and the low back - Du Zhong is one of the classic herbs for lumbar soreness, weak knees, and fatigue rooted in deficiency.
  • Calms the fetus and steadies pregnancy - traditional use includes threatened miscarriage with back pain, restless fetus, and weak constitutional support.
  • Gently supports yang and structural resilience - unlike harsher hot tonics, Du Zhong is valued for being steady, nourishing, and relatively moderate.

Classic Formulas

  • Du Huo Ji Sheng Tang - classic chronic bi formula that relies on Du Zhong to strengthen the underlying Liver-Kidney deficiency.
  • Shou Tai Wan - fetus-calming formula in which Du Zhong supports pregnancy when the lower back is weak and the fetus is insecure.
  • Kidney-deficiency formulas for soreness and weakness often pair Du Zhong with Xu Duan, Gou Ji, or Sang Ji Sheng.

Classical Text References

  • Traditional herbology consistently presents Du Zhong as a sweet warm bark that enters the Liver and Kidney to strengthen the back, knees, and fetus.
  • Its combination of tonifying and fetus-calming actions makes it unusually versatile compared with many other Kidney tonics.
  • Classical texts value it for weakness and instability, not for acute excess pain patterns by themselves.