This species is closely related to Datura inoxia[].

Common Name: Thorn Apple

General Information

Datura metel is an erect, often much-branched, annual to short-lived perennial plant growing up to 2 metres tall[].
Although toxic, thorn apple is a popular traditional medicine and is commonly harvested from the wild for local use. It is sold in markets, both for traditional use and as a source of compounds for the pharmaceutical industry. The plant is also used as a pesticide and repellent. It is often grown as an ornamental in tropical to temperate areas of the world, particularly types with double flowers and purple flowers[, ].
Plants often become naturalized in waste areas in the tropics[].

Known Hazards

All members of this genus contain narcotic compounds and are very poisonous, even in small doses[, ].

Botanical References

,

Range

Originally native to the Americas, it is now found in many areas of the world, from the warm temperate zone to the tropics.

Habitat

Waste places, river sands etc in sunny positions[, ]

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Annual/Perennial
Height	1.50 m
Pollinators	Hawkmoths, Insects
Self-fertile	Yes
Cultivation Status	Ornamental, Wild

Cultivation Details

Prefers a rich light sandy soil[]. Grows best in a fertile calcareous soil[]. Prefers a well-drained soil in a partially shaded position[].
Plants usually start flowering about 4 months after sowing the seed, at which time the first harvest can be taken[]. Several more harvests are possible at intervals of 1 - 2 months[].
Fruits are harvested when ripe[].
In India, yields per hectare of 10.5 - 14.5 tonnes of fresh plant material and 750 - 1,200 kg of seeds have been reported[].
There are a number of named varieties selected for their ornamental value[].
The flowers have an exotic fragrance, though the bruised leaves have an unpleasant smell[].

Edible Uses

The leaves and roots are bruised, mixed with water and left to stand for several hours. The liquid is then drawn off and drunk. This is a highly narcotic drink, producing a stupefying effect that it is not easy to remove[]. Caution is advised, see the notes above on toxicity[].

Medicinal

Thorn apple is a bitter narcotic plant that relieves pain and encourages healing[]. It has a long history of use as a herbal medicine, being especially well-known as a treatment for chest complaints, including asthma, cough, tuberculosis and bronchitis. It is a very poisonous plant, however, and is subject to legal restrictions in some countries[]. It should be used with extreme caution and only under the supervision of a qualified practitioner since all parts of the plant are very poisonous and the difference between a medicinal dose and a toxic dose is very small[, , ]. Excess doses cause giddiness, dry mouth, hallucinations, coma amd death[].
The plant contains the alkaloids hyoscyamine, hyoscine and atropine[]. Total alkaloid content of the leaves is 0.426%, which is mainly atropine[]. The seeds contain 0.426% alkaloids, which is mainly hyoscyamine[]. The roots contain 0.35% hyoscyamine[]. The alkaloid content in tetraploid plants is almost double that of diploid plants[].
Hyoscyamine and scopolamine are anticholinergics. They act by competitively and reversibly inhibiting the neuro-transmitter acetylcholine from binding to its muscarinic receptors, and this antagonism leads to sympathomimetic-like effects in the organs. They increase the heart rate, induce relaxation and motor inhibition in smooth muscles, decrease secretions, and induce dilation of the pupils of the eyes. Although at low doses their action tends to be depressant and sedative, at high doses they cause substantial excitation: agitation, disorientation, exaggerated reflexes, hallucinations, delirium, mental confusion and insomnia[].
Hyoscyamine is used to provide symptomatic relief of various gastrointestinal disorders including spasms, peptic ulcers, irritable bowel syndrome, pancreatitis, colic and inflammation of the bladder. It has also been used to relieve some heart problems, to reduce excess saliva production and control some of the symptoms of Parkinson’s disease[].
Scopolamine is used in ophthalmology to dilate pupils, as an analgesic and to prevent motion sickness[].
Atropine dilates the pupils and is used in eye surgery[].

The whole plant, but especially the leaves and seed, is abortifacient, anaesthetic, anodyne, antiasthmatic, antispasmodic, antitussive, bronchodilator, hallucinogenic, hypnotic and mydriatic[, , , ]. It has a wide range of applications, including in the treatment of asthma, epilepsy, hysteria, insanity, heart diseases, fever with catarrh, diarrhoea, skin diseases etc[, , ]. Different parts of the plant are used in various preparations for sedating patients with mental disorders[].
The dried flowers and leaves are cut into small chips and used in cigarettes as a treatment for a range of conditions, especially asthma and Parkinson's Disease[, ].
A poultice of the crushed leaves is used on conditions such as inflammatory swellings and rheumatic joints in order to relieve pain[, ]. The leaves are also applied externally to treat conditions such as haemorrhoids, boils, sores, skin diseases, rheumatism, headache, toothache and ear ache[].

An extract of the flowers is used as an anaesthetic - 3 - 5g applied orally produces a general anaesthesia within 5 minutes and lasting 5 - 6 hours[].

The seed oil is used for massaging painful body parts[].

Agroforestry Uses:

Datura species are extremely susceptible to the various viruses that afflict the potato family (Solanaceae), it can act as a centre of infection so should not be grown near potatoes or tomatoes[].

Other Uses

The plant is widely used as a pesticide[]. Plant extracts have been used successfully against caterpillar pests in forestry, cotton pathogens and domestic vermin such as fleas and jigger, and to reduce insect damage in stored wheat and maize[].
The plant extracts have proved useful to control the root knot nematode, Meloidogyne javanica[].
An extract made from the roots is sprinkled in houses to repel snakes[].
The seeds, mixed with sorghum flour, are used as poison bait for rats[].

The leaves are used to dye cloth green[].

The seed contains about 16% oil with an approximate fatty acid composition of palmitic acid 14%, oleic acid 30% and linoleic acid 52%[]. The oil also contains considerable quantities of sterols (about 13.4 g/kg) and tocopherols (about 3.4 g/kg) which are considered to be of medicinal interest[].

Propagation

Sow the seed in individual pots in early spring in a greenhouse[]. Put 3 or 4 seeds in each pot and thin if necessary to the best plant. The seed usually germinates in 3 - 6 weeks at 15°c. Plant out in late spring or early summer, after the last expected frosts.
Especially in areas with hot summers, it is worthwhile trying a sowing outdoors in situ in mid to late spring.