Home / Chinese Herb / CINNAMON BARK [肉桂, ROU GUI]


Name : Cinnamon Barkcinnamonbark

Chinese Name : 肉桂

Latin Name : Cortex Cinnamomi


This herb is the dried bark of the trunk of Cinnamomum cassia Presl. Or C. japonicum Sieb. of the family Lauraceae. It is mainly grown in the Guangdong, Guangxi, Yunnan, and Taiwan provinces of China and other states in Southeast Asia. The bark is stripped off the tree in summer and dried after the cork is scraped. It is then sliced or ground into powder.

Cinnamon bark is a Cold-dispelling and pain-relieving agent. Traditionally, it has been used as a stomachic to invigorate the flow of Qi and blood, to relieve pain,and as a stimulant, carminative, astringent, sedative, and tonic. Today,cinnamon bark is used as a stomachic and for gastrointestinal ailments. It is considered a good antiaging medicinal herb.

Use of Cinnamon Bark in TCM

Pungent and sweet in taste, and hot, it acts on the kidney, spleen, heart, and liver meridians.

Effects, Medicinal Uses, and Combinations

  1. Disperses Wind-Cold exopathogens and induces diaphoresis: to treat colds, headaches, and associated symptoms, cinnamon bark is combined with pubescent angelica root (du huo), loranthus, and eucommia bark. Also, it is used with Chinese angelica root, cnidium (chuan xiong), carthamus, fresh ginger, and evodia to treat menstrual disorders, amenorrhea, and menorrhalgia.
  2. Invigorates the kidney yang : for lumbago and chronic asthma due to kidney-yang deficiency, cinnamon bark is used with fu zi (processed aconite), poria, Chinese yam, alisma, and processed rehmannia, as in Shen Qi Wan.
  3. Relieves aches and pains: to treat body aches and pains, lumbago due to Cold, and stagnation of Qi and blood, cinnamon bark is blended with pubescent angelica, loranthus, and eucommia bark.
  4. Regulates gastrointestinal disorders: for indigestion,chronic gastritis, diarrhea,and cold limbs and stomach, cinnamon bark is combined with processed aconite, ginger root, poria, and aucklandia root, as in Guei Zhi Wan.


In a decoction of 1 to 5 g, or 0.05 to 1 g if powdered form is used.


The herb is hot and pungent, and may induce bleeding. People with syndromes of hyperactivity due to yin deficiency. Heat of the excess type in the interior, or pregnant women should not use the herb or use it with caution.

Side Effects and Toxicity

No adverse side effects or toxicity were reported at the therapeutic dose. The chemically active ingredient, cinnamaldehyde, is potent and large doses have caused spasms, motor imbalance, polypnea, and death due to paralysis.

Chemical Constituents

Cinnamon bark contains up to 1 to 2 percent volatile oil, tannins, catachins, proanthocyanidius, resins, mucilages, gum, sugar, and calcinoxide. The major ingredient in the oil is cinnamic aldehyde (cinnamaldehyde). Other constituents include cinnamyl acetate, phenylpropyl acetate, eugenol, cinnamic acid, eugenol acetate, safrol, cinnamyl alcohol, and other alcohols. Z-hypdroxycinnamaldehyde has been isolated from the bark as a natural product.

Pharmacological Findings

Cinnamon bark possesses the following pharmaceutical actions :

  1. Cinnamon bark is carminative and astringent. The essential oil has carminative and antiseptic properties.
  2. Cinnamaldehyde, the major component of the volatile oil of the bark, is a sedative, antipyretic,and analgesic in animals. It causes dermatitis in humans.
  3. Relieves bronchial asthma.
  4. Cinnamon oil has been demonstrated to be antifungal, antiviral, antimicrobial, and larvicidal. It inhibits the growth of coli, S. aureus, and Candida albicans.
  5. Cinnamon oil is a strong stomachic, increases the secretion of digestive juices, and relieves spasms in the digestive tract. Prevents abnormal fermentation in the intestines and prevents ulcer formation in mice.
  6. Regulates blood circulation and enlarges blood vessels. The herb’s decoction significantly increased coronary flow in the isolated hearts of guinea pigs.