Inrō – Travel Pharmacy

Inrō was the Ninja’s first-aid kit. With this equipment, he mixed his poisons and medicines together.


A Ninja was adept at mixing poisons and drugs and was able to extract poison from plant, animal, or mineral products.

Poison could be used to kill an opponent, but more often it was used to paralyze, stun, or incapacitate the opponent.

Knowing whether a poison worked quickly or slowly was important to complete the job. Sometimes it was necessary for an opponent to be silent immediately, other times the Ninja wanted to get to safety before the poison took effect.

Ninja knew all kinds of poisons, some smeared on their weapons, others mixed with food or drink, or released as poison gas. It is even said that flowers were poisoned.

A simple method was to drag the weapons through horse manure before use. An opponent wounded with these weapons often developed muscle cramps shortly after being wounded and died of blood poisoning.

A strange poison (gyokuro) was made from green tea buried in the ground for 30 to 40 days. Then this mixture was mixed with soya bean paste. If this drink was given to a sick person, they would die within a few days. It could take a month for a healthy person, but after 70 days they too died from the effects of the disease.

A poison was made from green plums or peaches that was known for its quick lethal effects (zagarashijaku).

The Ninja were probably also the inventors of poison gas, even if it was not usually used to kill, but only to stun. A little of this gas in the air and all the guards would become sluggish or fall asleep. So the Ninja could do his job without being bothered.

One of these sleeping gases was made from the blood of a newt, a snake, and a mole. The tincture was then absorbed by a leaf. If you burned this paper, everyone would fall asleep from the smoke.

In another sleeping gas, three powdered male rats, some paulownia tree leaves, a centipede, and a handful of cottonseeds were mixed together and the mixture pressed into a spherical shape. When this bullet was burned, anyone inhaling the fumes fell into a deep sleep.

The Ninja made a liquid narcotic from ground hemp leaves, which he then mixed into tea.

In order to paralyze an opponent and incapacitate him, the Ninja often used liquid or body liquids from toads, pufferfish, or other poisonous animals.

To prevent an opponent from pursuing, the Ninja liked to use itching medicine made from stinging nettle.

There is also said to have been a mushroom which, when eaten, gave the victim a fit of laughter and was easily overpowered.

A horrific poison, the manufacture of which few people know today, was capable of driving a person insane. The only thing that can be made known to the public is that five to ten seeds of a plant were ground into powder and mixed with the food.

There are a large number of plant poisons that are common in nature and were easy for the Ninja to obtain. Contemporary poisonous plants include Arum, broom, henbane, bean, Christmas rose, yew, aconite, foxglove, spotted hemlock, germer, gold lacquer, laburnum, autumn crocus, dog parsley, potato, tree of life, lupine, lily of the valley, oleander, spindle tree, castor bean, red bryony, sallow tree, common buttercup, celandine, daphne, datura, deadly nightshade, water hemlock, cypress spurge.

Many of these poisons are not very dangerous, but with the right pharmacological knowledge and the right mixture, dangerous poisons can be made from them.

One important aspect should always be considered: the dose makes the poison. Any food is a poison in the right amount. And in small doses, poison can even be used as a medicine, as is done in homeopathy.

No one can say for sure how many people have been killed by poison over time. But this has certainly happened very often because poison used to be a surefire means of changing the succession of thrones or influencing politics. The medical examinations were still very poor at that time, and one could rarely recognize poisoning by a few clear signs.

Even today, forensic doctors assume that a not inconsiderable number of deaths can be traced back to poisoning, which is usually not discovered if the person was already of advanced age because then a forensic medical examination is omitted. Undoubtedly, the heirs slowly and undetectably killed people they didn’t like over a longer period of time with small doses of poison.

Remedies and Healing Methods

Since the Ninja were usually on their own for a long period of time, they had to be able to take care of themselves medically. He was able to heal minor as well as major injuries, poisoning, or evil.

He treated sword wounds with a mixture of goatsfoot and black cowpea. Sometimes he would also put crushed narcissus roots on the wound. He used a paste of wheat flour and water to relieve bamboo cuttings, especially the pain. Monkshood, calamus, hemp, and chrysanthemums were used as painkillers. The Ninja placed crushed leeks on bullet wounds. To stop the blood flow from minor scratches, he uses the smoke from smoldering scraps of cloth. A mixture of tannin and Indian ink was applied to scalded skin to soothe it. If the Ninja had a major bleeding wound, he would use a mixture of chewed tea leaves and dry, powdered paulownia leaves. Various plants such as Japanese acacia, mugwort, peony, and thuja species could be used to stop bleeding. For sprains and strains, he used philodendron amurense half crushed and half raw, mixed it with vinegar, and applied it to the skin. To combat wound infection, the Ninja put fish skin on the wound and changed it from time to time.

If he ate spoiled food, he ate the same food again in a charred form.

The Ninja are said to have been able to fight cancer. A branch of an old wisteria tree, preferably with growth, was ground into powder, mixed with water, and drunk. The intake of three grams of water nut seed powder or water chestnut powder daily is said to have been used as a cancer cure.

Some Ninja also mastered the art of resuscitation. In Japanese shiatsu, fainting or other ailments can be alleviated or cured by massage and stimulation on certain parts of the body.


A Ninja always took an emergency ration with him on a mission. This consisted of rice, wheat flour, dried flour roots, dried trout, dried plums, and pine powder. Genmai juice, a drink made from unpolished rice, restored his strength.

To quench his thirst, the Ninja used peppermint powder and salt plums. If his water reserves were exhausted, he could also use a certain leek plant. 30 sesame seeds are said to have given him temporary relief from thirst.

The Ninja ate foods that were normal and common in their habitat. These included bean paste, buckwheat flour, fish, vegetables, prunes, sesame, tofu, unpolished rice, and other foods in the Japanese diet.

This menu is very difficult for a non-Japanese to stick to and takes some getting used to, but it doesn’t have to be. Hatsumi once said that the diet differs in different countries. The important thing is that you eat a balanced diet and don’t eat too much meat.

Text: Stefan Imhoff