Physic Nut

Physic nut (Jatropha curcas) is an upright shrub or small tree that is of the spurge family, Euphorbiaceae. It is native to Mexico, the Caribbean, Central America, and South America. It was introduced to many tropical and subtropical areas for its use as a garden ornamental, and is commonly found in southern Florida, Hawaii, southern Africa (Mozambique, Zambia, Transvaal, Natal), and throughout the warmer parts of Asia. Physic nut also grows in parts of Australia, where it is considered to be an invasive weed.

Physic Nut Toxic Components

Physic nut, like other members of the Jatropha genus contain highly toxic compounds. The main toxins in physic nut are curcin (similar to ricin in the castor oil plant, a type of phytotoxin (Phytotoxins or toxalbumins are large, complex protein molecules that resemble bacterial toxins, and as such are equally as toxic) and a purgative oil. When eaten, the toxins are released from the plant which are known to inhibit protein synthesis. Once the toxins are absorbed into the horse's blood stream, rapid multi-system organ failure follows close behind. Ingestion of physic nut is quickly fatal; within 15 to 20 minutes signs of toxicity start to appear. There is no antidote. Treatment is essentially symptomatic and supportive. Physic nut is usually avoided by horses, except during periods of drought and/or little other food is available to eat.

What Physic Nut Looks Like

Physic nut has thick, often greenish bark which exudes a watery sap when cut. It produces small, 5-petaled greenish-yellow flowers, borne in branched clusters. It develops dull yellow, hairless, capsule-like round fruits that turn dark brown when ripe; capsules split open to release two or three black seeds.