Datura
Datura stramonium
Datura SP.
SOLANACEAE
The Solanaceae include  more than 2,500 species of tropical and temperate regions, many from  South America (potato, tomato, peppers, tobacco) and the majority belong  to the genus Solanum.
The important species in  Western medicine are among the genera Datura, Atropa (deadly  nightshade), Hyoscyamus (henbane).
The datura are herbs,  rarely shrubs or shrubs, very poisonous. Some are decorated with  flowers and foliage, many grow spontaneously in the rubble, waste  places, bordering crops, roads and housing.
       
       
The datura stramonium is  cosmopolitan, other species are more localized;
D. metel
in India, Africa and  naturalized in the Mediterranean
D. Inoxia
tropical America
(Mexico and Caribbean)
D. suavolens,
D. arborea
South America,
D. sanguinea
in the Andean region.
The datura stramonium  (officinalis) is an annual plant with dark green leaves cut, flower  solitary, white, sometimes purple, large sizes (5 to 10 cm). The fruit is a spiny  capsule, as often in the Datura genus, containing many small seeds.
COMPOSITION AND CHEMICAL  PROPERTIES 
The datura and its  cousins belladonna and henbane have a similar chemical composition, 15  to 20% of minerals and especially 0.2 to 0.5% of tropane alkaloids (see  glossary) of hyoscyamine and scopolamine.
All parts of Datura  contain but in the leaves as the concentration is highest.
The hyoscyamine and  atropine have the same chemical formula and the same pharmacological  activity.
The first is optically  active, the second is not (racemic) and the latter is used in medicine,  although probably not present in the living plant.
They are  parasympathicolytiques (see glossary) that competitively inhibit the  reversible binding of acetylcholine receptors and thus provide an effect  apparently sympathicomimetic:
    * Fast enough tachycardia  with slightly increased blood pressure,
    * Decrease in bowel  movements, tone of the ureters and bile but increased the pressure in  the bladder, removal of bronchospasm due to acetylcholine,
    * Significant reduction  in secretions: saliva, sweat, bronchial, lacrimal, digestive,
    * Mydriasis (pupil  dilation) by progressive paralysis of the constrictor muscles of the  iris.
At toxic doses, there is  excitement central nervous system (CNS) with agitation, hallucinations,  delirium, confusion, low dose on the contrary, a trend sedative.
Scopolamine also affects  parasympathicolytique but less marked, with more cons net effects on the  CNS: sedative, hypnotic, with amnesia and depressive tendency. A high dose is a  disabling to coma.
USES 
The Datura is a  hallucinogenic plant that has been used at all times by the "sorcerers",  "Shaman" and "healing medium".
Its use is particularly  dangerous because the amount of leaf smoke or ingest for the  hallucinogenic effect is difficult to dose.
A high dose (equivalent  to some g leaf), delirium is furious with convulsions and coma and  sometimes death at low doses the effects are just  parasympathicolytiques.
Hallucinations fantastic  start 2 to 4 hours after eating and lasts several hours are powerful,  that "the grass of the devil", the draft of witches brew or initiation  (see "the grass and the little devil Smoke "by C. Castaneda).
In East Africa the datura  has been used as ordeal poison in "judgments of God," the ordeal.
In India many suicides or  poisoning criminals owed.
But the thorn is also a  medicinal herb, the dosage forms is country:
in France found the  powder datura, dyeing and soft extract of datura, there were the leaves  of datura.
The datura is much less  used belladonna in France, it is a component of cough syrups and entered  a few years ago in the composition of cigarettes and powder asthma.
This is an important  plant in homeopathy: datura 3DH sedative, antispasmodic 4DH asthma, 3CH  regulator of arterial circulation, 6CH bronchial disorders.
We will not detail the  particulars of tropane alkaloids extracted from Datura: atropine and  scopolamine.
    * Atropine:  premedication, ophthalmology, events and spasmodic pain in the digestive  tract and urinary tract.
    * Scopolamine:  premedication and parkinsonism, motion sickness (with the risk of  urinary retention in cases of prostate disorders).
More anecdotally, is  still used in tropical leaf datura dried fumigation to relieve the  asthma attack and the green leaf slightly heated poultice on painful  joints.
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