Senna

Senna, common name for a genus of the legume family, with about 260 species widely distributed in temperate and tropical areas. The genus contains shrubs and trees as well as annual and perennial herbs. The leaves are pinnately compound (feather-like) and the flowers often showy. Many are ornamental, and some woody tropical species are among the showiest of flowering trees.

Medicinal preparations used as purgatives are prepared from the dried leaflets of several species. The principal drug, Alexandria senna (also known as true senna or tinnivelly), was first introduced into Europe by Arabs, and consists of the leaves of the Alexandrian senna plant, often adulterated with stems and pods of the same plant, and leaves of other plants. A common laxative preparation of senna, called black draught or black dose, includes Epsom salts and extract of liquorice.

Scientific classification: Sennas belong to the genus Senna of the family Fabaceae (or Leguminosae). Alexandrian senna is classified as Senna alexandrina.