Black Henbane: The Hallucinogenic Intoxicator

By kallummcdonald – no rights reserved (CC0)

Black henbane is a toxic herb that has been employed for both medicine and criminal intoxication (Alizadeh et al., 2014). For instance, a man named Dr. Crippen poisoned his wife before flying to the United States to meet with his mistress in 1910. Additionally, an accidental poisoning of inmates in a monastery caused a “delirious frenzy” accompanied by hallucinations which turned the institution a lunatic asylum (Grieve, n.d.).

Dosage

All parts of Black Henbane including the leaves, seeds, and roots are toxic (Alizadeh et al., 2014). No amount of boiling can get rid of its toxicity. Small amounts can cause intoxication symptoms such as dizziness and delirium. Unless it is administered in a controlled environment under supervision, authorities should be called immediately after ingesting or touching this plant. For example, eating as many as 4 flowers, which grow to about 2 inches in diameter, is enough to cause clinical manifestations in young children around 3-5 years old (Utah State University, n.d.).

Organoleptics

Henbane, especially the leaves, have an extremely foul odor and bitter taste (Utah State University, n.d.; Alizadeh et al., 2014). As a result, it is rarely accidentally eaten by humans and animals. However, the roots have a weaker smell and taste and have been mistaken for salsafry, chicory, and parsnips (Grieve, n.d.). For example, a woman mistakenly picked up Henbane roots believing them to be parsnips Then she boiled them and made a soup that she fed her family. All nine people became intoxicated and had symptoms of blurred vision, giddiness, sleepiness, and ultimately, delirium and convulsions.

Constituents

Toxic alkaloids in Black Henbane include hyoscyamine, atropine, tropane and scopolamine (Alizadeh et al., 2014). They are found in all parts of the herb. The most toxic part of the plant is the seeds which are 10 times stronger than the leaves (Grieve, n.d.). The main alkaloids, hyoscyamine and scopolamine, are employed in medicines and serve as mild analgesics, antispasmodics, sedatives, and mydriatics.

Route of Administration

Intoxication can occur from any contact with the plant, especially with the seeds (Alizadeh et al., 2014). Touching, smelling, drinking, or eating the plant can cause intoxication. Smelling the seeds, for instance, can cause intake of large amounts of toxic alkaloids. Also, touching this plant can cause skin irritation and dermatitis (Utah State University, n.d.). In the past, necklaces with the herb were worn by children to stop convulsions because of its strong sedative effects.

Detection

Diagnosis of henbane poisoning is done through presentation of symptoms, especially anticholinergic syndrome and hallucinations (Alizadeh et al., 2014). According to Alizadeh et al., manifestation of intoxication includes several symptoms such as “… mydriasis, tachycardia, arrhythmia, agitation, convulsion and coma, dry mouth, thirst, slurred speech, difficulty speaking, dysphagia, warm flushed skin, pyrexia, nausea, vomiting, headache, blurred vision and photophobia, urinary retention, distension of the bladder, drowsiness, hyperreflexia, auditory, visual or tactile hallucinations, confusion, disorientation, delirium, aggressiveness, and combative behavior…” (Alizadeh et al., 2014).

Antidote and Intervention

The most common treatment for henbane poisoning is gastric emptying and giving activated charcoal and benzodiazepines (Alizadeh et al., 2014).

References

Alizadeh, A., Moshiri, M., Alizadeh, J., & Balali-Mood, M. (2014). Black henbane and its toxicity – A descriptive review. Avicenna Journal of Phytomedicine, 4(5), 297–311. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4224707/

Grieve, M. (n.d.). Henbane. A Modern Herbal. Retrieved January 21, 2023, from https://www.botanical.com/botanical/mgmh/h/henban23.html

Utah State University Extension. (n.d.). Black Henbane. Extension. Retrieved January 21, 2023, from https://extension.usu.edu/rangeplants/forbsherbaceous/black-henbane#:~:text=All%20plant%20parts%20of%20black,pulse%2C%20convulsions%2C%20and%20coma.