The truth of Ninja -Ninja Encyclopedia-

The Secret Medicines of Ninjas

The meaning of medicine and poison for the ninja

Flower of aconite

The flower of the aconite tree

Ninjas lived in the deep mountains, where various type of plants grow. Ninjas lived a life unified with nature and had a deep knowledge of vegetation. So, it is quite natural that Ninjas utilized many wild vegetation for their diet and medical treatment. Ninjas conducted peddling of medicine and went all around Japan. The main reason was to gather information about other countries. It can be said that Ninjas were well informed about medicine even as much as doctors.
It was very advantageous for ninjas that they could pretend to be doctors because doctors are someone that can get absolute credit from patients. In instances where the
relatives of their enemies were sick, ninjas could approach them as doctors and easily elicit important information from them. Not only that, in a lucky case, ninjas could kill their targets with poison. This is also one of the Ninjutsu (Ep) tacticsD
Poison was very convenient because even weak people can kill someone strong easily. Also, poison can increase the killing power of weapons. For instance, if a ninja painted the essence of aconite on the arrowheads or edge of knives, enemies could be killed from only wounds from scratches made by those weapons.
The raw materials for the medicine and poison existed all around ninjas so they could collect them easily. Ninjas could use medicine both in their usual lives and missions. In accordance with the idea of oriental medicine, healthy foods affect on people was as good as medicine. In short, ninjas could keep their health only by eating a healthy everyday and if they were injured in their missions, they could treat wounds with medicine. Further to this, there was wild grass that people can eat, ninjas could eat them when close to starvation only if they had knowledge about herbs.
Ninjas and plants with medicinal effects had an inseparable relationship.
Letfs looks at the kinds of herbs that ninjas actually used.

Herbs for medicine and edible grass

Flower of aconite



This was a wild grass that grew on roadsides or vacant lands. This was very useful as a painkiller or for its diuretic effect.



A grass with a natural property of sterilization and preservation from decay. The most important effect was treating stomatitis and sore throats.


The chameleon plant

A herb with an intense smell. Constipation can be treated by boiling and drinking it. This herb is also effective for curing the inflammation of wounds.



The leaves of perillas were used as a medicine for treating defervescence and regulating the bow function.


The mugwort

The leaves of the mugwort are herbal medicine, which have a hemostatic action. Dried young sprouts and stumps of the mugwort were used as a medicine for stomach pain, abdominal pain, diarrhea, anemia, poor circulation, if they were boiled and drunk.


Veitch's bamboo

It is said that the dried leaves of Veitch's bamboo were a medicine for the treatment of high blood pressure and diabetes if they were used as tea leaves.


Amur cork]tree

In the cuticle of the Amur cork]tree, medicinal properties can be extracted. This plant has strong antimicrobial activity, and can be used to treat pathogens typhoid, cholera, and dysentery. Moreover, it can be used to keep oneself alert and awake.


The strict secret medicine

This is made of iris, dried citrus peels, and ginseng. It can be used to treat analgesic, anthelmintic, abdominal pain, fever, pain, indigestion, cough and loss of willpower.



People can eat young bracken sprouts. The roots of bracken were dried and were used as the raw material for bracken rice cakes.


The Capsella bursa]pastoris

The leaves can be eaten.




This is a poison to kill rats. Ratsbane contains of arsenic and people can be killed with ratsbane too.


Zakarashi (͂炵)

This poison contains "amygdalin " found in unripe Ume (~) (plums) fruit. As amygdalin has a strong toxicity and there were Ume trees everywhere in Japan, ninja were able to acquire amygdalin easily from anywhere in Japan.


Poison in tea

This is the poison with ingredients from Japanese tea. Generally speaking, Japanese tea is good for your health because the properties in tea are good for our bodies. Catechin has an intense bactericidal action that kills germs in the stomach and tannin has the ability to fix the bowel. When these properties are produced in excess people get sick. Catechin devastates the gastrointestinal and tannin brings about indigestion.
" Poison in tea " is something that was used to take advantage of these effects from Japanese tea. Below states how this poison was made. At first, the ninja would insert dark green tea into a bamboo container and fill it to the ground. One month later, when taken out, the tea will have become poisonous. It is said that if a ninja made someone secretly drink a few drops of the liquid, even if they were healthy, they would be sick within a month, and they would be dead after a few months.

Osteopathy of Ninjas

acupuncture points(c{ Tsubo)

acupuncture points
(c{ Tsubo)

As ninjas were quite knowledgeable regarding oriental medicine, they did not have to depend upon medicine necessarily in order to maintain their health. In accordance with the a key principle of oriental medicine, the most important thing for health is harmonizing with nature. The less interference a person gets from substances ingested like taking drugs ,the better. Oriental medicine includes knowledge and treatment of" acupuncture points (c{ Tsubo) " , which are the biologically important points that exist throughout the whole body. Ninjas stimulated the points with acupuncture and moxibustion ( I Shinkyuu ) , or their fingers when they felt uncomfortable. They used other methods too such as stepping a piece of bamboo under the arch of the feet, or clasping acorns on their palms. Ninjas were always under heavy stress, massages were the best relaxation method for them. Health methods of Ninjas were not so different from oriental medicine that we utilize in the modern world now.