Aconitum napellus (
monk's-hood,
[2] aconite,
wolfsbane) is a
species of highly toxic 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 m (3 ft 3 in) tall, with hairless stems and leaves. The
leaves are rounded, 5–10 cm (2.0–3.9 in) 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 (0.39–0.79 in) 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 skin contact
.
Cultivation[edit]
Subspecies[edit]
- 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
- 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 sources[5][6])
- 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.
[7] 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.
[8] This species has been crossed with other Aconitums to produce attractive
hybrids for garden use, including
Aconitum × cammarum.
[9]
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.
[10] A. napellus has a long history of use as a poison, with cases going back thousands of years.
[11] 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.
[12] Aconites have been used more recently in murder plots; they contain the chemical alkaloids
aconitine,
mesaconitine,
hypaconitine and
jesaconitine, which are highly toxic.
[13]
Toxicology[edit]
Marked symptoms may appear almost immediately, usually not later than one hour, and "with large doses death is almost instantaneous."
[citation needed] Death usually occurs within two to six hours in fatal poisoning (20 to 40 mL of
tincture may prove fatal).
[14] 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.
[15] 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.
[14][16] The only post-mortem signs are those of
asphyxia.
[15]
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.
[19][20]
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.