Strychnos nux-vomica (PROTA)

Plant Resources of Tropical Africa Introduction

List of species

General importance
Geographic coverage Africa
Geographic coverage World
Fruit
Stimulant
Dye / tannin
Medicinal
Timber
Auxiliary plant
Food security

Strychnos nux-vomica L.

Protologue: Sp. pl. 1: 189 (1753).

Family: Loganiaceae

Chromosome number: 2n = 24, 44

• Crow fig, nux-vomica tree, poison nut, snake-wood, strychnine plant (En).
• Vomiquier, noix vomique, vomique officinale, pomme de voutac (Fr).
• Noz vômica, carimão (Po).

Strychnos nux-vomica originates from India and South-East Asia and is introduced and locally naturalized in tropical Africa. It is cultivated in Ghana and Sudan.

The medicinal use of Strychnos nux-vomica in Africa is limited. In Ghana the seeds are eaten to treat anaemia. The seed, bark, wood and roots have numerous applications in traditional medicine in Asia, Europe and the United States. In India the fruit is used in both the Ayurvedic and Unani systems of medicine and is considered acrid, pungent, bitter, poisonous and heating. It is used as an appetizer, tonic, astringent, aphrodisiac and antipyretic, and it is claimed to cure leucoderma, blood diseases, itching, ringworm, piles, ulcers, anaemia, jaundice, urinary discharges, joint pain, lumbago and weakness of limbs. In Europe a description of medicinal use of Strychnos nux-vomica dates back as early as 1540 A.D. It was especially used to treat nervous disorders and problems of the digestive organs and the respiratory system. Nowadays it is mainly used in phytotherapy to treat upset stomach, abdominal pain, constipation, hangover, heartburn, insomnia, circulatory problems, depression, migraine, nervous conditions, problems related to menopause and respiratory diseases.

In India the seeds are used for dying cloth pale brown. The seeds are an ingredient of liquors. The wood is hard and termite proof and is used in manufacturing furniture, cart wheels and agricultural implements. The leaves are used as a green manure.

The annual production of Strychnos nux-vomica seed in India was estimated at 2000 t at the beginning of the 1970s. In the period 1965–1971 the average production of strychnine and brucine from Strychnos nux-vomica seeds in India was 18,000 kg/year. Most of the alkaloids are exported to the United States and Europe.

All plant parts of Strychnos nux-vomica contain indole alkaloids, but the seeds have the highest concentration. They contain 1–3% alkaloids, mainly strychnine and its dimethoxylated derivative brucine. The other plant parts contain several other strychnine derivatives with a total concentration of up to 1%: 12-hydroxy-strychnine, 15-hydroxy-strychnine, α-colubrine, β-colubrine, icajine, 11-methoxy-icajine, novacine, vomicine, pseudostrychnine, pseudobrucine, pseudo-α-colubrine, pseudo-β-colubrine, N-methyl-sec-pseudo-β-colubrine, and isostrychnine. The bisindole alkaloid longicaudatine has also been isolated; it has reserpine-like activity.

Strychnine is very toxic, and the lethal dose in humans may start at about 0.4 mg/kg. It may cause anxiety, restlessness, painful convulsions of the body, breathing difficulties and even death resulting from suffocation or exhaustion. In addition, long-term intake of even small amounts of strychnine can cause liver damage. Strychnine increases blood pressure, and it is applied in medicine as a stimulator of the nervous system and as a reliable anaesthetic. Brucine is about 50–100 times less toxic than strychnine. The seed extract exhibits significant analgesic, anti-inflammatory, anti-ulcer, cytotoxic, antioxidant and uterine stimulant activity. The analgesic and anti-inflammatory activities are caused by brucine and brucine N-oxide.

The analysis of cytotoxic effects of brucine, brucine N-oxide, strychnine and isostrychnine on human hepatoma cells showed that brucine exhibited the strongest toxic effect.

Galactomannans and galactans are also present in the seeds. The seed extract is efficient in the coagulation-flocculation of hydrophobic colloids (such as a clay suspension), but it is a poor flocculent in the case of hydrophilic colloids (such as bacteria). The leaves have strong allelopathic properties.

• Medium-sized tree up to 25 m tall; bole up to 100 cm in diameter; branchlets slightly short-hairy.
• Leaves opposite, simple and entire; stipules absent; petiole 5–15 mm long; blade orbicular to broadly elliptical or ovate, 5–18 cm × 4–13 cm, base rounded to cordate, apex shortly acuminate or acute, glabrous and shiny above, minutely hairy especially on veins beneath, 3–5-veined from the base.
• Inflorescence an axillary thyrse 3–7 cm long, many-flowered.
• Flowers bisexual, regular, 5-merous; calyx lobes ovate, outside densely hairy; corolla with a slender tube c. 1 cm long, abruptly widening at the throat, outside glabrous, inside sparsely woolly hairy in lower part, lobes narrowly ovate, c. 3 mm long, margin thickened and minutely hairy, greenish white to white; stamens inserted at the mouth of the corolla tube, exserted; ovary superior, ovoid, glabrous, style up to 1 cm long, stigma head-shaped.
• Fruit a globose berry 2–4(–6) cm in diameter, orange, glabrous, 1–4-seeded.
• Seeds lens-shaped to orbicular or ellipsoid, 20–23 mm × 18–20 mm × c. 4 mm, silky hairs.

Strychnos comprises about 200 species: about 60 species in Asia, 65 in America and 75 in Africa. Strychnos nux-vomica belongs to section Strychnos.

In its natural habitat Strychnos nux-vomica occurs at the edge of dense forest, on river banks and along the shore, mainly on loamy or loamy-sandy soil, although it also occurs on lateritic and clayey loam soils. The annual rainfall varies from 1200–3500 mm.

Strychnos nux-vomica regenerates from seeds and suckers. Seeds take 70–120 days to germinate. In India seeds are sown in nurseries and seedlings are transplanted to the field. Strychnos nux-vomica plants have been successfully regenerated from tissue culture.

Fruiting starts 10–15 years after planting. Fruits are usually gathered from the trees. Fallen fruits are considered to be of inferior quality. After collecting, seeds are cleaned and dried in the sun. Dried seeds can be stored in jute bags for a long period without loss of alkaloid content, but they should be kept in dry conditions to prevent deterioration by fungi. Seeds are further processed in factories to obtain strychnine and brucine. In traditional Chinese medicine, seeds are usually heated in oil to reduce their toxicity. This significantly reduces the contents of strychnine and brucine and increases the amounts of isostrychnine, isobrucine, strychnine N-oxide and brucine N-oxide.

Strychnos nux-vomica is widespread in its original area of distribution in India, Indo-China and Thailand and is not in danger of genetic erosion. In Africa virtually nothing is known about its distribution or genetic variability.

The use of Strychnos nux-vomica for medicinal purposes has diminished over the years. The use of strychnine has been superseded because of its high toxicity. Some of the other alkaloids may play a role in the development of new anti-cancer or anti-malarial drugs. More research into the chemical composition and pharmacological activities of these compounds seems warranted. In India the seeds are still widely used in traditional medicine and there is a need to develop high yielding, alkaloid-rich cultivars.

• Cai, B.C., Wang, T.S., Kurokawa, M., Shiraki, K. & Hattori, M., 1998. Cytotoxicities of alkaloids from processed and unprocessed seeds of Strychnos nux-vomica. Acta Pharmacologica Sinica 19(5): 425–428.

• Iwu, M.M., 1993. Handbook of African medicinal plants. CRC Press, Boca Raton, Florida, United States. 464 pp.

• Leeuwenberg, A.J.M. (Editor), 1980. Angiospermae: Ordnung Gentiales. Fam. Loganiaceae. Die natürlichen Pflanzenfamilien. Second Edition. Band 28 b-1. Duncker & Humblot, Berlin, Germany. 255 pp.

• Mshana, N.R., Abbiw, D.K., Addore-Mensah, I., Ekpere, J.A., Enow-Orock, E.G., Gbile, Z.O., Noamessi, G.K., Odei, M.A., Odunlami, H., Oteng-Yeboah, A.A., Sarpong, K., Sofowora, A. & Tackie, A.N., 2000. Traditional medicine and pharmacopoeia. Contribution to the revision of ethnobotanical and floristic studies in Ghana. Organisation of African Unity / Scientific, Technical and Research Commission. 920 pp.

• Purwaningsih, 1999. Strychnos L. In: de Padua, L.S., Bunyapraphatsara, N. & Lemmens, R.H.M.J. (Editors). Plant Resources of South-East Asia No 12(1). Medicinal and poisonous plants 1. Backhuys Publishers, Leiden, Netherlands. pp. 467–472.

• Yin, W., Wang, T.-S., Yin, F.-Z. & Cai, B., 2003. Analgesic and anti-inflammatory properties of brucine and brucine N-oxide extracted from seeds of Strychnos nux-vomica. Journal of Ethnopharmacology 88(2–3): 205–214.

• Bisset, N.G., 1989. Arrow and dart poisons. Journal of Ethnopharmacology 25: 1–41.

• Bisset, N.G. & Leeuwenberg, A.J.M., 1968. The use of Strychnos species in Central African ordeal and arrow poisons. Lloydia 31: 208–222.

• Cai, B., Nagasawa, T., Kadota, S., Hattori, M., Namba, T. & Kuraishi, Y., 1996. Processing of nux vomica. VII. Antinociceptive effects of crude alkaloids from the processed and unprocessed seeds of Strychnos nux-vomica in mice. Biological and Pharmaceutical Bulletin 19(1): 127–131.

• Corsaro, M.M., Giudicianni, I., Lanzetta, R., Marciano, C.E., Monaco, P. & Parrilli, M., 1995. Polysaccharides from seeds of Strychnos species. Phytochemistry 39(6): 1377–1380.

• Deng, X., Yin, F., Lu, X., Cai, B. & Yin, W., 2006. The apoptotic effect of brucine from the seed of Strychnos nux-vomica on human hepatoma cells is mediated via Bcl-2 and Ca²⁺ involved mitochondrial pathway. Toxicological Sciences 91(1): 59–69.

• Yin, W., Wang, T.-S., Yin, F.-Z. & Cai, B., 2003. Analgesic and anti-inflammatory properties of brucine and brucine N-oxide extracted from seeds of Strychnos nux-vomica. Journal of Ethnopharmacology 88(2–3): 205–214.

• P. Oudhia, SOPAM, 28-A, Geeta Nagar, Raipur, 492001, C.G., India

Oudhia, P., 2008. Strychnos nux-vomica L. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. Accessed 5 April 2025.

• See the Prota4U database.