Senna

Sonamukhi, the leaf of a small yellow-flowered shrub grown in India as Tinnevelly senna, whose sennosides are a well-studied laxative for occasional use.

Senna alexandrina, long known in trade as Cassia angustifolia, is a small shrub of the pea family with pale grey-green leaflets, yellow flowers and flat, papery pods. It is grown in India as Tinnevelly senna, and this pack prints its dried leaf as Sonapata.

The leaf contains sennosides, which bacteria in the large bowel turn into compounds that stir it to move. The evidence is strong: the European Medicines Agency accepts senna leaf for short-term use in occasional constipation. It also says that use beyond a week calls for medical advice, that long use can upset the bowel's own rhythm and the body's salts, and that it is not for children under twelve, or in pregnancy or breastfeeding.

• Occasional constipation
• Stimulant laxative
• Source of sennosides