Gelsemium is a genus of flowering plants belonging to family Gelsemiaceae. The genus contains three species of shrubs to straggling or twining climbers. Two species are native to North America, and one to China and Southeast Asia.
Carolus Linnaeus first classified G. sempervirens as Bignonia sempervirens in 1753; Antoine Laurent de Jussieu renamed the genus in 1789. Gelsemium is a Latinized form of the Italian word for jasmine, gelsomino. G. elegans is also nicknamed "heartbreak grass".
All three species of this genus are poisonous.
The active components of gelsemium are the alkaloids, which are present in a concentration of about 0.5%. These consist primarily of gelsemine (a highly toxic compound related to strychnine), with lesser amounts of related compounds (gelsemicine, gelsedine, etc). Other compounds found in the plant include scopoletin (also called gelsemic acid), a small amount of volatile oil, fatty acid and tannins.
As late as 1906, a drug called gelsemium, made from the rhizome and rootlets of Gelsemium sempervirens, was used in the treatment of facial and other neuralgias. It also proved valuable in some cases of malarial fever, and was occasionally used as a cardiac depressant and in spasmodic affections, but was inferior for this purpose to other remedies.
- G. elegans. Heartbreak grass. Twining climber, native to India, Indonesia, Laos, Malaysia, northern Myanmar, Taiwan, northern Thailand, Vietnam, and the Chinese provinces of Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Jiangxi, Yunnan, and Zhejiang. Found in scrubby forests and thickets from 200–2000 meters elevation.
- G. rankinii. Rankin's Jessamine, Swamp Jessamine, Rankin's Trumpetflower. Native to southeastern United States.
- G. sempervirens. Yellow Jessamine, Carolina Jessamine, Evening Trumpetflower. Native to southeastern United States from Virginia to Texas and south through Mexico to Guatemala. It is commonly grown as a garden flower worldwide.
Alleged poisoning victims
- In December 2011 Chinese billionaire Long Liyuan was killed when the cat-stew that he was eating was allegedly poisoned with Gelsemium elegans.
- A lawyer for the deceased's life insurance company told a pre-inquest hearing that toxicology reports had identified traces of gelsemium in the body of Alexander Perepilichny. Perepilichny died outside his UK home on 10 November, 2012 after warning of Kremlin death threats related to Magnitsky affair 
Symptoms of poisoning
Arthur Conan Doyle, writer of the Sherlock Holmes series, once administered himself a small amount of gelsemium and kept increasing the amount every day until he could no longer stand the ill effects. In a letter written by him to the British Medical Journal on 20 September 1879, he described that he had persistent diarrhoea, severe frontal headache, and great depression, and therefore stopped his self-experimentation at 200 minims.
- Lewis, Leo (2012-01-04). "A purrfect murder? Tycoon killed by poisoned cat stew". The Times. Retrieved 2012-01-04.
...the fatal dose of Gelsemium elegans, a highly poisonous plant known as 'heartbreak grass'
- Wenkert et al., Journal of Organic Chemistry (1962) v.27, pp.4123-4126
- Przybylska, M., Acta Crystallogr. (Copenhagen) (1962) v.15: pp.301-309.
- "Gelsemium". New International Encyclopedia. 1906.
- China tycoon "ate poisoned cat-meat stew", BBC
- Russian whistleblower had traces of rare poison in stomach, plant expert says, The Guardian
- "Alexander Perepilichny: Rare Chinese poison found in stomach of Russian whistleblower". ABC News. 20 May 2015. Retrieved 2 June 2015.
- "Gelsemium". Botanical.com. Retrieved 2 June 2015.
- Devlin, Hannah (18 May 2015). "Gelsemium: the plant that can cause convulsions, paralysis and asphyxia". The Guardian. Retrieved 2 June 2015.
- Gibson, J.M., and R. L. Green, eds. 1986: University of Iowa Press. Letters to the Press: Arthur Conan Doyle.
- Doyle, Arthur Conan (20 September 1879). "Arthur Conan Doyle takes it to the limit (1879)". British Medical Journal. BMJ Publishing Group Ltd. Retrieved 2 February 2014. (subscription required (. ))
- Doyle, Arthur Conan (20 September 1879). "Letters, Notes, and Answers to Correspondents". British Medical Journal. BMJ Publishing Group Ltd. Retrieved 2 February 2014. (subscription required (. ))