''Aconitum napellus'', monkshood, aconite, Venus' chariot or wolfsbane, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of highly

toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...

flowering plants in the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

Aconitum ''Aconitum'' (), also known as aconite, monkshood, wolfsbane, leopard's bane, devil's helmet, or blue rocket, is a genus of over 250 species of flowering plants belonging to the family (biology), family Ranunculaceae. These herbaceous perennial ...

'' of the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Ranunculaceae Ranunculaceae (, buttercup or crowfoot family; Latin "little frog", from "frog") is a family (biology), family of over 2,000 known species of flowering plants in 43 genera, distributed worldwide. The largest genera are ''Ranunculus'' (600 spec ...

, native and

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to western and central Europe. It is an

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of ...

perennial plant In horticulture, the term perennial (''wikt:per-#Prefix, per-'' + ''wikt:-ennial#Suffix, -ennial'', "through the year") is used to differentiate a plant from shorter-lived annual plant, annuals and biennial plant, biennials. It has thus been d ...

growing to tall, with hairless stems and leaves. The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are rounded, diameter, palmately divided into five to seven deeply lobed segments. The

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s are dark purple to bluish-purple, narrow oblong helmet-shaped, tall. Plants native to Asia and North America formerly listed as ''A. napellus'' are now regarded as separate species. The plant is extremely poisonous in both ingestion and body contact. It is the most poisonous plant in all of Europe.

Cultivation

''Aconitum napellus'' is grown in gardens in

temperate zone In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ra ...

s for its spiky

inflorescences In botany, an inflorescence is a group or cluster of flowers arranged on a plant's stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a main axis ( pe ...

that are showy in mid-autumn, and its attractive foliage. There are white and rose colored forms in cultivation too. The

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

'Spark's Variety' has gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. It includes the full range of cultivated p ...

Subspecies

Nine

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

are accepted by the ''Flora Europaea'': *''Aconitum napellus'' subsp. ''napellus'', south-western Britain *''Aconitum napellus'' subsp. ''corsicum'' (Gáyer) W.Seitz, Corsica *''Aconitum napellus'' subsp. ''firmum'' (Rchb.) Gáyer, Central and eastern Europe (declared as an own species '' Aconitum firmum'') *''Aconitum napellus'' subsp. ''fissurae'' (Nyár.) W.Seitz, Balkans to south-western Russia *''Aconitum napellus'' subsp. ''hians'' (Rchb.) Gáyer, Central Europe *''Aconitum napellus'' subsp. ''lusitanicum'' Rouy, south-western Europe *''Aconitum napellus'' subsp. ''superbum'' (Fritsch) W.Seitz, western Balkans *''Aconitum napellus'' subsp. ''tauricum'' (Wulfen) Gáyer, Eastern Alps, southern Carpathians (declared as an own species '' Aconitum tauricum'' by other sourcesThe Plant List (KEW)
''Aconitum tauricum''
(2018-05-03)Jäger et al.: ''Rothmaler - Exkursionsflora von Deutschland'', Bd. 2. Ed. 20, Spektrum akadem. Verlag.) *''Aconitum napellus'' subsp. ''vulgare'' (DC.) Rouy & Foucaud, Alps, Pyrenees, northern Spain

Uses

''Aconitum napellus'' is grown in gardens for its attractive spike-like inflorescences and showy blue flowers. It is a cut flower

crop A crop is a plant that can be grown and harvested extensively for profit or subsistence. In other words, a crop is a plant or plant product that is grown for a specific purpose such as food, Fiber, fibre, or fuel. When plants of the same spe ...

used for fresh cutting material and sometimes used as dried material. The species has a low natural propagation rate under cultivation and is propagated by

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

or by removing offsets that are generated each year from the rootstocks. The use of micropropagation protocols has been studied. This species has been crossed with other Aconitums to produce attractive hybrids for garden use, including ''Aconitum × cammarum''. Like other species in the genus, ''A. napellus'' contains several

poison A poison is any chemical substance that is harmful or lethal to living organisms. The term is used in a wide range of scientific fields and industries, where it is often specifically defined. It may also be applied colloquially or figurati ...

ous compounds, including enough cardiac poison that it was used on spears and arrows for hunting and battle in ancient times. Persian physician

Avicenna Ibn Sina ( – 22 June 1037), commonly known in the West as Avicenna ( ), was a preeminent philosopher and physician of the Muslim world, flourishing during the Islamic Golden Age, serving in the courts of various Iranian peoples, Iranian ...

(980–1037) wrote that arrows dipped in the sap were used to kill, and Dr Antonio Guaineri, in one of the first medical dictionaries 'Practica', wrote that arrows that had the poison from roots of the plant were used to kill wild goats in Italy. ''A. napellus'' has a long history of use as a poison, with cases going back thousands of years. During the ancient Roman period of European history, the plant was often used to eliminate criminals and enemies, and by the end of the period it was banned and anyone growing ''A. napellus'' could have been legally sentenced to death. Aconites have been used more recently in murder plots; they contain the chemical alkaloids

aconitine Aconitine is an alkaloid toxin produced by various plant species belonging to the genus ''Aconitum'' (family Ranunculaceae), commonly known by the names wolfsbane and monkshood. Aconitine is notorious for its toxic properties. Structure and rea ...

, mesaconitine, hypaconitine and jesaconitine, which are highly toxic. It was also used in a recent

Sherlock Holmes Sherlock Holmes () is a Detective fiction, fictional detective created by British author Arthur Conan Doyle. Referring to himself as a "Private investigator, consulting detective" in his stories, Holmes is known for his proficiency with obser ...

book plot.

Toxicology

Marked symptoms may appear almost immediately, usually not later than one hour, and "with large doses, death is almost instantaneous". Death usually occurs within two to six hours in fatal poisoning (20 to 40 mL of

tincture A tincture is typically an extract of plant or animal material dissolved in ethanol (ethyl alcohol). Solvent concentrations of 25–60% are common, but may run as high as 90%.Groot Handboek Geneeskrachtige Planten by Geert Verhelst In chemistr ...

may prove fatal).''The Extra Pharmacopoeia Martindale''. Vol. 1, 24th edition. London: The Pharmaceutical Press, 1958, page 38. The initial signs are

gastrointestinal The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascular system. ...

including nausea,

vomiting Vomiting (also known as emesis, puking and throwing up) is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteritis, pre ...

, and

diarrhea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...

. This is followed by a sensation of burning, tingling, and numbness in the mouth and face, and of burning in the abdomen. In severe poisonings pronounced motor weakness occurs and cutaneous sensations of tingling and numbness spread to the limbs.

Cardiovascular In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart a ...

features include

hypotension Hypotension, also known as low blood pressure, is a cardiovascular condition characterized by abnormally reduced blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood and is ...

, sinus bradycardia, and ventricular

arrhythmia Arrhythmias, also known as cardiac arrhythmias, are irregularities in the cardiac cycle, heartbeat, including when it is too fast or too slow. Essentially, this is anything but normal sinus rhythm. A resting heart rate that is too fast – ab ...

s. Other features may include sweating, dizziness, difficulty in breathing, headache, and confusion. The main causes of death are ventricular arrhythmias and asystole, paralysis of the heart or of the respiratory center. The only post-mortem signs are those of

asphyxia Asphyxia or asphyxiation is a condition of deficient supply of oxygen to the body which arises from abnormal breathing. Asphyxia causes generalized hypoxia, which affects all the tissues and organs, some more rapidly than others. There are m ...

. Treatment of poisoning is mainly supportive. All patients require close monitoring of

blood pressure Blood pressure (BP) is the pressure of Circulatory system, circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term ...

and cardiac rhythm. Gastrointestinal decontamination with

activated charcoal "Activated" is a song by English singer Cher Lloyd. It was released on 22 July 2016 through Vixen Records. The song was made available to stream exclusively on ''Rolling Stone'' a day before to release (on 21 July 2016). Background In an inter ...

can be used if given within one hour of ingestion. The major physiological antidote is

atropine Atropine is a tropane alkaloid and anticholinergic medication used to treat certain types of nerve agent and pesticide poisonings as well as some types of slow heart rate, and to decrease saliva production during surgery. It is typically give ...

, which is used to treat bradycardia. Other drugs used for ventricular arrhythmia include

lidocaine Lidocaine, also known as lignocaine and sold under the brand name Xylocaine among others, is a local anesthetic of the amino amide type. It is also used to treat ventricular tachycardia and ventricular fibrillation. When used for local anae ...

amiodarone Amiodarone is an antiarrhythmic medication used to treat and prevent a number of types of cardiac dysrhythmias. This includes ventricular tachycardia, ventricular fibrillation, and wide complex tachycardia, atrial fibrillation, and paroxys ...

bretylium Bretylium (also bretylium tosylate) is an antiarrhythmic agent. It blocks the release of noradrenaline from nerve terminals. In effect, it decreases output from the peripheral sympathetic nervous system. It also acts by blocking K+ channels and ...

, flecainide, procainamide, and mexiletine.

Cardiopulmonary bypass Cardiopulmonary bypass (CPB) or heart-lung machine, also called the pump or CPB pump, is a machine that temporarily takes over the function of the heart and lungs during open-heart surgery by maintaining the circulation of blood and oxygen throug ...

is used if symptoms are refractory to treatment with these drugs. Successful use of charcoal hemoperfusion has been claimed in patients with severe aconite poisoning. Poisoning may also occur following picking the leaves without wearing gloves; the aconitine toxin is absorbed easily through the skin. In this event, there will be no gastrointestinal effects. Tingling will start at the point of absorption and extend up the arm to the shoulder, after which the heart will start to be affected. The tingling will be followed by unpleasant numbness. Treatment is similar to poisoning caused by oral ingestion and even handling the plant without gloves has been reported to result in multi-organ failure and death. The plant's chief toxic component,

, is a potent

neurotoxin Neurotoxins are toxins that are destructive to nervous tissue, nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insult (medical), insultsSpencer 2000 that can adversely affect function ...

that opens

tetrodotoxin Tetrodotoxin (TTX) is a potent neurotoxin. Its name derives from Tetraodontiformes, an Order (biology), order that includes Tetraodontidae, pufferfish, porcupinefish, ocean sunfish, and triggerfish; several of these species carry the toxin. Alt ...

sensitive sodium channels. It increases the influx of sodium through these channels and delays repolarization, thus increasing excitability and promoting ventricular dysrhythmias.

References

External links

* {{Authority control napellus Flora of the Alps Flora of Europe Plants described in 1753 Taxa named by Carl Linnaeus