Many botanical compounds have important medical uses, and some of modern medicine’s most important drugs were derived initially from plant sources.

However, some of these botanical compounds have a very narrow dosage range between a therapeutic effect and toxicity. This tight range of beneficial action is alternately referred to as the Therapeutic Index or the Therapeutic Window.

This concept certainly applies to a very interesting botanical that has been used throughout the ages and is present today in many homeopathic preparations.

Aconite is the usual reference to aconitum, a plant genius that resembles wild parsley or horseradish. There are 350 species of aconite that exist around the world, 170 in China alone. Many are found throughout Asia, Africa and Europe. More than 100 species are found in the temperate climates of both the United States and Canada.

Throughout the ages, aconite alternately has been referred to as monkshood, wolf’s bane, leopard’s bane, devil’s helmet and blue rocket.

In modern homeopathic medicine, aconite is used for general malaise, undefined weakness and to stimulate poor circulation. People with numbness in the extremities or poor circulation (as in cold hands and feet) use aconite preparations to stimulate circulation, hence its colloquial reference name of “blue rocket” to the variety that produces beautiful deep blue flowers. In the same way, aconite preparations are used to alleviate joint pain, inflammation and certain skin diseases by stimulating blood circulation throughout the body.

The mechanism of action appears to be the increased production of nitric oxide in the human body. There has been considerable interest recently in nitric oxide supplementation for athletes involved in performance sports to increase their exercise intensity and endurance.

Since aconite is readily absorbed through the skin, topical aconite preparations (liniments, creams and lotions) are available that are used as “counterirritants”, products that stimulate local blood circulation and produce localized warmth to relieve joint pain and the leg pain from sciatica.

However, it should be noted that aconite is a highly poisonous plant and small amounts of the pure plant are highly toxic. So the above-mentioned preparations contain very small, very defined quantities of aconite.

As little as 2mg of pure aconite or one gram of the plant can cause death! Even slight contact with the flowers can cause the fingers of one’s hand to become numb—a typical example of the therapeutic effect of aconite progressing to a toxic side effect with excessive exposure.

The therapeutic, as well as the lethal, compound in aconite is aconitine, a toxic alkaloid that generally accounts for about 1.5% of the dry weight of the plant.

Safe dosing of aconite tincture depends on meticulous processing of the plant using everything but the root, and pounding it into a pulp that can be pressed and mixed in alcohol to extract the aconitine alkaloid. Straining and diluting the resulting product will produce the desired homeopathic therapy, and a more concentrated tincture produces an interesting poison if you’re attempting to develop an unusual murder plot idea.

Symptoms of aconite poisoning include nausea, vomiting, sweating, breathing difficulties and heart problems. Death usually results from paralysis of the respiratory system or cardiac arrest.

Although aconite can be lethal when applied to the skin, smaller doses are deadly when taken orally, and any oral dose beyond the therapeutic range will cause burning and tingling of the lips, tongue, mouth and throat. Numbness of the throat will follow, with difficulty in speaking, blurred vision and an interesting green-yellow vision distortion.

This last side effect would make for an interesting clue in a murder scene when deciding to use an aconite preparation to kill off a character in your murder mystery.

Thoughts? Comments? I’d love to hear them!