Colocynthis

Colocynthis is a genus of flowering plants in the family Cucurbitaceae. The genus comprises a small number of species native to arid regions of Africa, the Middle East, and parts of Asia. In many sources, the best-known species is Colocynthis citrullus, commonly treated as Citrullus colocynthis, which is widely known as colocynth or bitter apple.

Description: These are annual or perennial herbaceous climbers or scrambling vines with deeply lobed leaves. Flowers are yellow and small. Fruits are hard, spherical to oblong berries with a thick rind when ripe; the pulp is pale and very bitter; seeds are numerous.

Chemical constituents and toxicity: Colocynthis fruit contains cucurbitacins, especially cucurbitacins C and related compounds, which account for the extreme bitterness and high toxicity. Ingestion can cause severe vomiting, diarrhea, abdominal pain, dehydration, electrolyte disturbances and, in severe cases, death. Handling can also cause skin irritation for some individuals, and large quantities are not safe for traditional medicines.

Uses: Historically, crushed fruit or extracts have been used as a drastic laxative and purgative in traditional medicine and as a nematicide or insecticide in some contexts. Modern medicine generally discourages internal use due to toxicity; any medicinal use requires qualified supervision and standardized preparations.

Taxonomy note: Colocynthis is sometimes treated as a synonym or subgenus of Citrullus colocynthis; classifications vary among sources.

Habitat and cultivation: Native to arid and semiarid regions, it tolerates drought but requires heat and sun; it is often found in deserts, scrublands, and roadside habitats. It is cultivated rarely as an ornamental or for research in some arid regions.