Theory of diseases treated with cassia twig and rhubarb

Woodcut illustration from an edition of 1833 (13th year of Daoguang reign period of Qing dynasty). The image and text give an account of the principles of diseases treated with decoction of cassia twig and rhubarb (guizhi jia dahuang tang), and the therapeutic effects of the individual ingredients of this remedy. When external malignance (xie) in the taiyang channel is not alleviated, and turns to heat and enters the interior of the body, the external symptoms become less pronounced than at the initial stage, and therefore cassia twig is administered rather than rhubarb. When the malignance has only just entered the stomach, and stomach fire is not yet extremely dry or intense, rhubarb is used without the addition of trifoliate orange (zhishi) or magnolia bark (houpo). If the external malignance has not been expelled, and the malignance is already in the stomach, a combined decoction of cassia twig and rhubarb is given to release it.

When external malignance lingers in the taiyang channel, the head aches and the neck is stiff as in the beginning, and therefore one should continue with the original prescription of cassia twig decoction. This is the recipe for semi-external, semi-internal taiyang channel syndrome. The stomach is the organ of the yangming channel. When the malignance has entered the stomach, rhubarb is added. Bladder. Organ of the taiyang channel.