Pharmacology and Medicinal Herbs

The Ninja and Medicinal Herbs

It is said that the Shinobi of Iga and Koga were very knowledgeable about medicinal herbs and toxic grasses. They are even supposed to have been specialized in the detection and research of toxic ingredients for judicial inquiries and autopsies!

When dealing with modern western medicines we can know the ingredients at once, but with herbal medicines it is truly difficult to understand what the active ingredient is and at times can be very mysterious. The active ingredient of the plant or herb in “Kampo” or Chinese medicine recipes is often unknown.

Historical documents tell us that many ninja became merchants of medicines, travelling the country selling their goods. It is without a doubt that they were well versed in the knowledge of medicinal herbs and poisonous plants.

In the Koga (Koka) area there have been many pharmaceutical companies since the beginning of the Edo Period in 1603 so researchers at the local Iga Ueno University are now paying quite a bit of attention to the relationship between Iga/Koga ninja and Japanese medicine.

However, just because the ninja was very familiar with the knowledge of herbal medicine, does not mean that pharmacology was more developed in Iga and Koga because of them. Medicine became popular there because a wide variety very strong medicinal herbs were naturally found there. The herbal tradition of the Iga and Koga area is said to long predate the history of ninjutsu.

While historically ninjutsu was a totally comprehensive martial art for survival including skills such as swordsmanship, magic, fire arts, astronomy and so on. Pharmacology would definitely have been one of the standard arts. In the martial arts it is necessary to maintain a healthy body, so medicine was critical to correct injuries and diseases.

Obviously, poisons can be used on missions for assassinations or even used to manipulate people.

The regions of Iga and Koga which produced a lot of the historical ninja were also close to the old capital. So, information was easy to obtain, yet they were surrounded by mountains and difficult to attack. Medicinal herbs and poisonous plants still grow in great abundance to this day in these areas. The very famous Mochizuki family of ninja descent still runs their own pharmacy today in Koga.

In the field of pharmacology, the Chinese have a long history of research and experimentation. It is said that the Chinese sage Shennong ate every kind of flower to verify its efficacy, and compiled one of the world 's oldest books, "Shennong’s Classic on Herbal Medicine" (神農本草経).

In it he divided herbs and plants into 3 categories:
Non-toxic long-term ingestion medicine
Poison-resistant curing medicine
Diarrheal drugs that are strongly poisonous and impossible to take long term

He classified all the plants and herbs which were later to become the drugs and poisons of future generations. At this time, Japan was still in its “Kofun” period (250 ~ 538 AD), and does not have the pharmacology history that China can boast.

But when looking at the connection between the ninja and the Shugenja, it is easy to understand that Chinese arts, sciences and culture were usually brought to Japan from the continent by Buddhist monks and then spread among the lay people of the areas they preached in.

In the Koga area, ninja used to say “Doku ni mo nari eru yojo-yaku” (毒にもなり得る養生薬). This means that poisons can at times also be medicine.

The origins of the classification of poisons and medicines began with the rule that a grass can work advantageously for a person and cause positive health effects while another grass can cause negative health effects or even death.

I hope this may have peaked your interest in the relationship between the ninja and herbal medicines.

Sean Askew

17 AUG 2017