Ishida Sanyaku (Ishida medicinal powder) (石田散薬)
Ishida Sanyaku was medical powder made and sold by the home of the parents of Toshizo HIJIKATA, a vice chief of the Shinsengumi (a paramilitary group of pro-shogunate ronin formed in Kyoto). The powder was considered to work for bonesetting, bruise, muscle pain, and cut. There is a legend that a Kappa Myojin (a deity of Kappa, an imaginary creature) taught them the production method.
Gyukakuso' (a plant of a buckwheat family, scientific name: Polygonum Thunbergii) that had been grown along the area of the Asakawa river, which was a tributary of the Tamagawa river, near Hijikata's house, was its raw material. It was harvested only on the Midsummer Day of the Ox (that falls sometime in late July or early August, traditionally considered the hottest period of the year).
Harvested Gyukakuso is dried under the sun to reduce the weight to one tenth. The dried Gyukakuso is charred and put into an iron pan. Sake is sprinkled over the Gyukakuso and it is dried again. Lastly, it is powered with a yagen (a tool used to grind Chinese medicine).
Ishida Sanyaku had a unique dose method. The medicine should be taken with warmed Japanese sake, instead of water. The dosage was specified as 3.75g a dose, or a day.
In 1948, in response to its manufacturing license application with the enforcement of amendments to the Pharmaceutical Affairs Law, the Ministry of Health and Welfare concluded that all charred medicines, including the Ishida Sanyaku, did not meet government criteria for efficacy, saying 'any clinical, scientific researches into their components, qualities and efficacy have not been carried out.'
On the other hand, there was an old man who insisted that he would never take any medicine but Ishida Sanyaku.
The Tosizo HIJIKATA museum still has a little Ishida Sanyaku at the time of discontinuation of manufacturing.
People of the Hijikatas say, 'it's too old, too scary to take this medicine.'
Gyukakuso itself is a herbal medicine that works for rheumatism, hemostatic, and pain relief. However, when it was charred for Ishida Sanyaku, such efficacy was considered to become ruined.