Gui Zhi

Cinnamomi Ramulus, Cinnamon Twigs


The decoction is orally taken at a normal dosage of 1.5-6g and at a large dosage up to 15-30g.


LD50 (mice/herb decoction/oral): 624.7mg/kg (administered during day), and 773.6mg/kg (administered at night).

Chemical Composition

Cinnamaldehyde; Beizylbenzoate; Cinnamyl acetate; (-cadinene; Calamenene; Coumarin. (1)


Contraindications: febrile diseases, fire hyperactivity due to yin deficiency, bleeding, and pregnancy.


Bi-directional regulatory effects on body temperature

Gui Zhi and Shao Yao used together have a unidirectional effect of raising body temperature. (2) , (3)

Protective effects against myocardial ischemia/re-perfusion damages

Research shows that cinnamic acid, an active component of Gui Zhi, has the following effects: 1) raising the recovery rate of the maximum per-stroke output index after myocardial ischemia and re-perfusion, 2) increasing the coronary flow after re-perfusion, 3) decreasing the leakage of LDH and CPK from cytosomes, 4) reduce the MDA content in myocardial tissues after re-perfusion, and 5) raising the activity of GSH. The distillation of Gui Zhi (1.5ml/L) can reduce the number of incidences of re-perfusion ventricular fibrilation. It also can improve various cardiac functions, such as recovering the heart rate, and increasing the maximum ventricular systole speed, the function index of the left ventricle, and the intake of cardiac muscles. (4) , (5)

Treating viral polymyositis

In one experiment, 40 guinea pig models of Coxsackie virus B1-induced polymyositis induced by Coxsackie virus B1 were randomly divided into 3 groups and treated as follows: group A (15 guinea pigs) was treated with Cai Hu, group B (15 guinea pigs) was treated with Gui Zhi, and group C (10 guinea pigs) served as a control group. The results showed that the symptoms, mylkinase spectrum, and pathological changes of both groups A and B had significantly improved, while those of group C had deteriorated, indicating that Cai Hu and Gui Zhi have a therapeutic effect on polymyositis in mice. (6)

Inhibitory effects on bacterial plaques

One study treated 60 cases of bacterial plaque with the distillation of Gui Zhi, and reported a 44.60% decrease in bacterial plaque index. Furthermore, the distillation of Gui Zhi has styptic and analgesic effects on patients with odontopathy. (7)

Invigorating pulse

Experiments show that Gui Zhi can significantly promote temperature and microcirculation recovery in mice of blood stasis due to cold. This effect of Gui Zhi is more pronounced than that of Dan Shen. (8)


  1. Editorial Committee of Chinese Materia Medica. State Drug Administration of China. Chinese Materia Medica. Shanghai: Science and Technology Press; 1998.
  2. Chen Hong, et al. China Journal of Experimental Recipes. 1998;4(1):13-16.
  3. Chen Hong, et al. China Journal of Experimental Recipes. 1999;5(1):12-15.
  4. Chen Fei, et al. China Jounral of Medicine. 1999;14(1):68-69.
  5. Zou Li Yan, et al. Journal of Beijing TCMl University. 1997;20(2):22-25.
  6. Chu Xu Hua, et al. China Journal of New Herbal Medicine and Clinical Practice. 1998;17(60):327-328.
  7. Wu Guo Hai, et al. Journal of Pharmacy Practice. 1998;16(6):337-338.
  8. Lu Chao, et al. Shanghai Journal of TCM. 1993;(12):34-36.