International Chinese Medical Journal of Daytona

Gui[4] Zhi[1] "Cinnamon twigs" Ramulus Cinnamomi Cassiae
Properties: acrid sweet warm
Channels: Lung Urinary Bladder Heart
Functions: Promotes sweating and dispels Wind and Cold. Used in formulas for treating Wind-Cold deficiency or Wind-Cold excess patterns.
Activates Yang Qi in the meridians to dispel Wind-Cold Damp for Bi/ Arthritis patterns
Activates Yang Qi of the bladder. Used in combination with other herbs to remove phlegm-fluid congestion and reduce edema and difficult urination. It can be used post-partum for difficult urination with no pain.
Activates Yang Qi in Chest. Can be used in combination with other herbs to treat cold phlegm fluid accumulation/ chronic bronchitis, Chest Bi syndrome/ Heart disease with chest pain and pressure, palpitation and cold, Irregular pulse due to Heart Yang deficiency with slow irregular pulse and pale, puffy watery tongue
Activates Yang Qi and blood in Ren and Chong meridians. Used in combination with other herbs to increase fertility in women who are infertile due to Yang deficiency, reduce painful menstruation that is characterized by low to moderate bleeding and less pain with heat application (take one weed before menstruation and then 3 days), and treat masses from blood stasis in the lower abdomen.
Dosage for decoction: Dosage: 3-10g up to 12 g
Caution and contraindication: not for use with heavy menstrual periods or pregnancy not for use in severe Heat conditions e.g. fever
References:
1. Lecture and notes from Pharmacopoeia I 1999. Dr. Li Jin LAc, OMD of the Su & Jin Family Acupuncture and Herb Clinic. p. 3

Chinese Pharmacopoeia Index