These plants are shrubs of 40-60cm in height with erect stems. They have alternately integrated paripinnate leaves, with leaflets arranged in opposite pairs.

The flowers, grouped together in axial clusters, look like a calyx, with 5 similar-sized sections (sepals) and a bright yellow corolla composed of 5 brown-veined petals.

The dehiscent fruit is a flat and smooth legume, containing between 6 to 8 seeds and is separated by the pericarp's thickening parenchyma tissue.

These are species found in areas that surround the deserts of Africa and Asia, as they require a warm temperature and climate that does not drop below 10ºC.

COLLECTION AND PRESERVATION

Branches are collected and sun dried shortly before the fruit matures; the leaflets are then separated from the legumes.

PART USED

Leaves (leaflets) and fruit.

ACTIVE INGREDIENTS

The plants active ingredients derive from anthracenes (free anthraquinones: rein, chrysophanol and aloemodine; heterosides; sennosides A, B, C and D); they also contain falvonoides.

PROPERTIES AND INSTRUCTIONS

This plant has been used since ancient times for its laxant and purgative properties, although the way it works has not been completely explained.

When taken orally, senna's heterosides are hardly absorbed at the small intestine stage. The active area is in the colon where it increases intestinal transit in the following way: the enzymes of the bacterial flora hydrolyse the O-heterosides, freeing the genines, which irritate the nerve endings of the intestinal wall.

Its laxant or purgative action depends on the dose used for each case. Excessive doses may cause intestinal colic and vomiting. It is used as an herbal tea for temporary constipation and also for situations when the intestines need to be emptied.

ACKNOWLEDGED TRADITIONAL USE

Laxative for the large intestine, which is used for cases of constipation and illness such as: anal fissures, haemorrhoids, etc., when defecation of soft faeces is advisable. (European Commission, ESCOP)

WELL ESTABLISHED USE

For temporary constipation. (EMEA)

PRECAUTIONS

Must not be used if suffering from ileus, during pregnancy or breast-feeding.

COMBINATIONS

Senna is usually combined with plants that have antispasmondic and carminative actions in order to reduce intestinal problems.

PRESENTATION

It is normally found as an herbal tea in teabags.

DID YOU KNOW ?

C. angustifolia is cultivated in the South of India (in the region of Tinnevelly), where nearly all the commercially used plants come from, and C. acutifolia in Sudan. Even though the senna fruit contains a slightly higher amount of anthracenosides than the leaf, it has a somewhat more gentle action and is preferred by people who may have a very sensitive intestine. This is due to the fruit containing less aloemodin.