Jimson weed is one of the over 3,000 members of the Solanaceae family many of which contain the alkaloids atropine (dl-hyoscamine) and scopolamine (hyoscine). The plant family Solanaceae is one of the largest families in the plant kingdom. Included in this family are edible species such as the potato (Solanum tuberosum L.), eggplant (Solanum melongena L.) and the tomato (Solanum lycopersicum). The family also includes ornamental plants of the genera Brunfelsia, Cestrum, Nicotiana and Datura among many others.
Jimson weed is of the Datura genus (Datura stramonium) which produces trumpet-like flowers in a variety of colors. There are more than a dozen species of this naturalized Asian plant. The plant has stout, much-branched, leafy stems from 2 to 5 feet high and large, smooth, thin, wavy, toothed leaves are from 3 to 8 inches long. The flowers, which appear from May to September, are white, funnel-shaped, about 3 inches long, and have a pronounced odor. The prickly seed pods which follow are about the size of a horse chestnut. When ripe these pods burst open, scattering numerous poisonous black, kidney-shaped seeds.
All parts of the plant are toxic and have been ingested, smoked or topically absorbed. The exact concentration of the alkaloids varies with species cultivation, environment, temperature, moisture and storage. The highest concentration occurs in the seeds with approximately 0.1 mg atropine per seed.
Other related plants
Other members of the Solanaceae family have tropane alkaloids. The Deadly Nightshade (Atropa belladonna) is one of the most famous and hence the name belladonna alkaloids for the anticholinergic tropane alkaloids found in these plants. Information about this plant can be found at http://www.botanical.com. In 1833 atropine was isolated from this plant. Other members of the Datura genus include fastuosa (purple hindu datura) and Toloache (Datura inoxia) from Mexico. Very closely related is the Brugmansia genus which generally are much larger plants than the Datura genius and includes the Angel's Trumpet.
Habitat and range
This is a very common weed in fields and waste places almost everywhere in the United States except in the North and West and widely disturbed throughout the world.
Epidemiology and Social History
The plant has been described throughout history as a toxin famous for its mind altering properties. There are references to it in Homer's Odyssey and Shakespeare plays. In the Americas the most reported account is from 1676 when some of the Jamestown settlers were near death after eating Datura stramonium (hence the name Jamestown weed) and then began using the plant for medicinal purposes, primarily as a sedative. Other Datura species have similar social histories. An extract of Datura metel, sometimes called Hindu Datura, was used as knockout drops to lure virgins into prostitution and then used by prostitutes on their clients. The Roman army in Asia Minor was severely crippled by deaths caused by eating a Datura species. Indians in Columbia used another Datura species for infanticide.
Accidental exposures have been reported by gardeners from ingestions of plant parts mistaken for other herbs. Even accidental exposure during routine gardening chores have resulted in "Gardener's Mydriasis" and "Cornpicker's Pupil". These exposures may result in mydriasis for several days. Intentional misuses by teenagers who eat seeds, drink tea or smoke cigarettes made of Jimson Weed have been reported.
Folklore
Atropine and scopolamine have long been associated with withchcraft. Various authors have traced the use of these substances to place victims into trans like states. The plants of the datura, nightshade, mandrake and henbane are known as hexing herbs.
Pharmacology
The toxins in Jimson Weed are tropane alkaloids which possess strong anticholinergic properties. They include atropine (d,l hyoscyamine) (leaves, roots, seeds), hyoscine (roots), and scopolamine (l-hyoscine). They act as competitive antagonists to acetylcholine at muscarinic receptors and effect sweating, salivation and smooth muscles. As tertiary amines they also have central nervous system absorption and result in a central anticholinergic syndrome of acute psychosis and delirium.
These toxins are easily absorbed from the GI tract. Atropine has a half-life of 4 hours. Metabolism occurs in the liver by hydrolysis which eliminates approximately half of the dose with the remainder excreted unchanged in the urine.
Medicinal
As herbal medications various preparations have been used over the years. Chinese herbal medicines that contain tropane alkaloids have been used to treat asthma, chronic bronchitis, pain, and flu symptoms.
Atropine has commercial preparations such as Donnagel, Donnatal, Hycodan, Lomotil, Lonox, Minims, Neo-Diophen, Urised, Butibel among other names. Atropine has been used in ophthalmic solutions and is available as oral and intravenous medications. It is used in the treatment of bradycardia and first degree heart block. Atropine is an important antidote in anticholinesterase poisoning.
Scopolamine is available in dermal patches for motion sickness as well as oral doses of the hydrobromide salt. It may be used as a preanesthetic medication and the treatment of some gastrointestinal disorders.
Toxicity
Ingestion of these anticholinergic alkaloids results in toxicity that presents with "Red as a beet, dry as a bone, blind as a bat, mad as a hatter" symptoms. These would include incoherent speech, impaired coordination, rapid heart beat, dilated pupils, blurred vision and dry, flushed or hot skin. In extreme cases users can experience seizures, intense visual or auditory hallucination, or cardiac arrest.
Toxicity from plants manifests as classic anticholinergic poisoning with symptoms in 30-60 minutes and may continue for 24-48 hours if left untreated as the alkaloids delay gastric emptying and absorption. Accidental contamination of food with these plant preparations has been reported in Paraguay teas, hamburger, honey and homemade wines. The amount of each alkaloid present in the plant varies among species, time of the year, location and part of the plant. As little as one-half teaspoon of Datura seed has caused death from cardiopulmonary arrest. An estimated lethal dose is > 10 mg atropine or > 2-4 scopolamine for an adult. In 2002 the MMWR reported a suspected intoxication with Moonflower by 14 teenagers in Ohio. All survived with supportive care.
Clinically physostigmine can be used as an antidote for the CNS manifestations of anticholinergic toxicity however it is only used in severe cases where other co-ingestants are not present. GI decontamination is the first line treatment with activated charcoal. If seizures are present, a benzodiazepine may be applicable.
References
- Electronic version of "A Modern Herbal" by Maud Grieve. Jimson Weed information
- Cornell University information on Jimson Weed
- MMWR 52(33);788-791, August 22, 2003.
- University of Illinois
- Haddad, Shannon & Winchester, Poisoning and Drug Overdose, Chapter 26 "Poisonous Plants", Third Edition, W.B. Sanders Co., 1998.
- RC Dart, Medical Toxicology, Third Edition, Lippincott, Williams & Wilkins, Chapter 255 "Plants", 2004.