|Plant in flower, Austria|
Aconitum napellus (monkshood, aconite, wolfsbane, fuzi, monk's blood) is a species of flowering plant in the genus Aconitum of the family Ranunculaceae, native and endemic to western and central Europe.
It is an herbaceous perennial plant growing to 1 metre tall, with hairless stems and leaves. The leaves are rounded, 5–10 cm diameter, palmately divided into five to seven deeply lobed segments. The flowers are dark purple to bluish-purple, narrow oblong helmet-shaped, 1–2 cm tall.
Plants native to Asia and North America formerly listed as A. napellus are now regarded as separate species.
A. napellus is grown in gardens in temperate zones for their spiky inflorescences that are showy in early-mid summer, and their attractive foliage. There are white and rose colored forms in cultivation too. The cultivar 'Spark's Variety' has gained the Royal Horticultural Society's Award of Garden Merit.
Nine subspecies are accepted by the Flora Europaea:
- Aconitum napellus subsp. napellus. Southwest England.
- Aconitum napellus subsp. corsicum (Gáyer) W.Seitz. Corsica.
- Aconitum napellus subsp. firmum (Rchb.) Gáyer. Central and eastern Europe.
- Aconitum napellus subsp. fissurae (Nyár.) W.Seitz. Balkans to southwest Russia.
- Aconitum napellus subsp. hians (Rchb.) Gáyer. Central Europe.
- Aconitum napellus subsp. lusitanicum Rouy. Southwest Europe.
- Aconitum napellus subsp. superbum (Fritsch) W.Seitz. Western Balkans.
- Aconitum napellus subsp. tauricum (Wulfen) Gáyer. Eastern Alps, southern Carpathians.
- Aconitum napellus subsp. vulgare (DC.) Rouy & Foucaud. Alps, Pyrenees, northern Spain.
Aconitum napellus is grown in gardens for its attractive spike like inflorescences and showy blue flowers. It is a cut flower crop 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 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 poisonous compounds, including enough cardiac poison that it was used on spears and arrows for hunting and battle in ancient times. 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, mesaconitine, hypaconitine and jesaconitine, which are highly toxic.
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 may prove fatal). The initial signs are gastrointestinal including nausea, vomiting, and diarrhea. 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 features include hypotension, sinus bradycardia, and ventricular arrhythmias. 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.
Treatment of poisoning is mainly supportive. All patients require close monitoring of blood pressure and cardiac rhythm. Gastrointestinal decontamination with activated charcoal can be used if given within one hour of ingestion. The major physiological antidote is atropine, which is used to treat bradycardia. Other drugs used for ventricular arrhythmia include lidocaine, amiodarone, bretylium, flecainide, procainamide, and mexiletine. Cardiopulmonary bypass 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.
Aconitine is a potent neurotoxin that opens tetrodotoxin sensitive sodium channels. It increases influx of sodium through these channels and delays repolarization, thus increasing excitability and promoting ventricular dysrhythmias.
- Chappuis, E. (2014). "Aconitum napellus". IUCN Red List of Threatened Species. Version 2014.1. International Union for Conservation of Nature. Retrieved 18 June 2014.
- "RHS Plant Selector - Aconitum 'Spark's Variety'". Retrieved 17 July 2013.
- Datta, Subhash Chandra. 1988 Systematic botany. New Delhi: Wiley Eastern Ltd.
- A. A. Watad, M. Kochba, A. Nissim and V. Gaba, "Improvement of Aconitum napellus micropropagation by liquid culture on floating membrane rafts", Journal Plant Cell Reports, Publisher: Springer Berlin / Heidelberg, ISSN: 0721-7714 (Print) 1432-203X (online), Issue Volume 14, Number 6 / March 1995, DOI 10.1007/BF00238594, pages 345–348
- Armitage, A. M. 2000. Armitage's garden perennials a color encyclopedia. Portland, Oregon: Timber Press. Pages 19–20.
- J Ethnopharmacol. 1981 Nov;4(3):247-336. Arrow poisons in China. Part II. Aconitum--botany, chemistry, and pharmacology. Bisset NG.
- "Toxicology in the Old Testament: Did the High Priest Alcimus Die of Acute Aconitine Poisoning?" Authors: Moog F.P.1; Karenberg A.1 Source: Adverse Drug Reactions & Toxicological Reviews (now known as Toxicological Reviews), Volume 21, Number 3, 2002 , pp. 151–156(6) Publisher: Adis International
- Roberts, M. F., and Michael Wink. 1998. Alkaloids biochemistry, ecology, and medicinal applications. New York: Plenum Press. Page 18.
- The Extra Pharmacopoeia Martindale. Vol. 1, 24th edition. London: The Pharmaceutical Press, 1958, page 38.
- One or more of the preceding sentences incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Aconite". Encyclopædia Britannica 1 (11th ed.). Cambridge University Press. pp. 151–152.
- Chan TY (April 2009). "Aconite poisoning". Clin Toxicol (Phila) 47 (4): 279–85. doi:10.1080/15563650902904407. PMID 19514874.
- Chyka PA, Seger D, Krenzelok EP, Vale JA (2005). "Position paper: Single-dose activated charcoal". Clin Toxicol (Phila) 43 (2): 61–87. PMID 15822758.
- Lin CC, Chan TY, Deng JF (May 2004). "Clinical features and management of herb-induced aconitine poisoning". Ann Emerg Med 43 (5): 574–9. doi:10.1016/j.annemergmed.2003.10.046. PMID 15111916.
- Aconite, Aconitum napellus - Resource for aconitum napellus seed & information
- Flora Europaea: Aconitum napellus
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