Toxicity
All parts of Datura plants contain dangerous levels of the tropane alkaloids atropine, hyoscyamine and scopolamine which are classified as deliriants, or anticholinergics. There is a high risk of fatal overdose amongst uninformed users, and many hospitalizations occur amongst recreational users who ingest the plant for its psychoactive effects.
The amount of toxins varies widely from plant to plant. There can be as much as a 5:1 variation across plants, and a given plant's toxicity depends on its age, where it is growing, and the local weather conditions. Additionally, within a given datura plant, concentrations of toxins are higher in certain parts of the plant than others, and can vary from leaf to leaf. When the plant is younger, the ratio of scopolamine to atropine is approximately 3:1; after flowering, this ratio is reversed, with the amount of scopolamine continuing to decrease as the plant gets older. This variation makes Datura exceptionally hazardous as a drug. In traditional cultures, a great deal of experience with and detailed knowledge of Datura was critical in order to minimize harm. An individual datura seed contains about 0.1 mg of atropine, and the approximate fatal dose for adult humans is >10 mg atropine or >2–4 mg scopolamine.
Datura intoxication typically produces delirium (as contrasted to hallucination); hyperthermia; tachycardia; bizarre behavior; and severe mydriasis with resultant painful photophobia that can last several days. Pronounced amnesia is another commonly reported effect. The onset of symptoms generally occurs approximately 30 minutes to an hour after smoking the herb. These symptoms generally last from 24 to 48 hours, but have been reported in some cases to last as long as 2 weeks.
As with other cases of anticholinergic poisoning, intravenous physostigmine can be administered in severe cases as an antidote.
Read more about this topic: Datura Stramonium