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Foxglove (Digitalis purpurea).
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Foxglove - Digitalis purpurea
Digitalis purpurea (foxglove, common foxglove,
purple foxglove or lady's glove) is a species of flowering plant in the plantain
family Plantaginaceae, native to and widespread throughout most of temperate
Europe. It is also naturalised in parts of North America and some other
temperate regions. The plants are well known as the original source of the heart
medicine digoxin (also called digitalis or digitalin).
Digitalis purpurea is an herbaceous biennial or short-lived perennial plant. The
leaves are spirally arranged, simple, 10–35 cm (3.9–13.8 in) long and 5–12
cm (2–5 in) broad, and are covered with gray-white pubescent and glandular
hairs, imparting a woolly texture. The foliage forms a tight rosette at ground
level in the first year.
The flowering stem develops in the second year, typically 1–2 m (3.3–6.6 ft)
tall, sometimes longer. The flowers are arranged in a showy, terminal, elongated
cluster, and each flower is tubular and pendent. The flowers are typically
purple, but some plants, especially those under cultivation, may be pink, rose,
yellow, or white. The inside surface of the flower tube is heavily spotted. The
flowering period is early summer, sometimes with additional flower stems
developing later in the season. The plant is frequented by bees, which climb
right inside the flower tube to gain the nectar within.
The fruit is a capsule which splits open at maturity to release the numerous
tiny 0.1-0.2 mm seeds.
The plant is popular as a garden subject, and
numerous cultivars have been developed with a range of colours from white
through pink to purple, such as "Dalmatian Purple". Cultivated forms
often show flowers completely surrounding the central spike, in contrast to the
wild form, where the flowers only appear on one side. D. purpurea is easily
grown from seed or purchased as potted plants in the spring.
The Latin name, digitalis comes from the word digitanus, meaning finger for the
thimble shaped flowers that look like you could fit your finger right inside.
Roman mythology associates the flower with Juno (Hera) who learned midwife lore
from the Goddess Flora, including a supernatural method of using foxgloves to
induce parthenogenetic (single-sex) pregnancy. Flora placed a foxglove blossom
on her thumb, touched Juno on the tips of her breasts & on her belly, so
that she became impregnated with Mars who had no father.
No matter what its name or legend, the plant is highly poisonous and, in the
right dosage, has the ability to severely affect the heart rate, possibly
causing death. Due to the presence of the cardiac glycoside digitoxin, the
leaves, flowers and seeds of this plant are all poisonous to humans and some
animals and can be fatal if ingested. Symptoms of Digitalis poisoning include a
low pulse rate, nausea, vomiting, and uncoordinated contractions of different
parts of the heart, leading to cardiac arrest and finally death.
Although foxglove is very dangerous
if misused, it has a long history of medicinal use for heart and
kidney problems, edema and aconite poisoning.
Extracted from the leaves, this same compound,
which is considered the beginning of modern therapeutics, whose clinical use was
pioneered in 1785 by William Withering, is used as a medication for heart
failure. He recognized it "reduced dropsy", increased urine flow and
had a powerful effect on the heart. Unlike the purified pharmacological forms,
extracts of this plant did not frequently cause intoxication because they
induced nausea and vomiting within minutes of ingestion, preventing the patient
from consuming more.
Legend says that Van Gogh used it to treat his
epilepsy.One of the interesting stories in the history of digoxin is the link
with Vincent Van Gogh. Much has been written about the physical and mental
health problems that Van Gogh had in his life and numerous diagnoses have been
proposed. Among these diagnoses is the suspicion that he suffered from digitalis
(foxglove) toxicity, which resulted in the frequent use of yellow halos in his
paintings due to xanthopsia. Supporting this hypothesis is the fact that when
Vincent painted his personal physician in the Portrait of Doctor Gachet he was
holding the foxglove plant.
An old saying about foxglove goes "It can raise the dead and it can kill
the living.
Source:
https://en.wikipedia.org/wiki/Digitalis_purpurea
https://theresagreen.me/2012/06/20/foxglove-fairytales-myths-medicine/
http://www.witchipedia.com/herb:foxglove
http://theconversation.com/weekly-dose-digoxin-the-heart-medicine
-that-may-have-given-us-van-goghs-starry-night-57980
