|
Senna
(Cassia angustifolia)
Description
Senna is a perennial plant that grows in rich soils in Southern
Arabia, India and the United States. The herb is traditionally
used for Constipation.
Herbal Uses
Senna leaf is stated to
possess cathartic (laxative) properties), (the leaf has greater
activity than the fruit) and is traditionally used for Constipation.
Suggested Intakes
Part of the herb used: Leaves
(or pods).
Leaf powder 0.5-2.0g daily.
Supplemental Uses
Laxative:
Senna is recommended for the relief of occasional or non-persistent
Constipation. The laxative action of the anthraquinone-containing
compounds of senna are well documented. The purgative (laxative)
action of the sennosides is now fairly well understood. Sennosides
are hydrolysed by the intestinal bacteria and then reduced
to give the active compound (anthrone).
Sennosides A and B and their
metabolites are reported to act on the large intestine, accelerating
colonic transport. These compounds also encourage the secretion
of water into the colon (1). Senna acts approximately 8-10
hours after being taken (2).
Nitric oxide synthetase
may also be involved in senna-induced fluid secretion and
Diarrhoea (3,4).
When compared to conventional
treatments, senna has been shown to be more effective as a
laxative (5,6).
Liver protection:
Some studies have shown that glycosides contained within senna
and related plant species have antihepatotoxic activity.
Safety and Precautions
Senna may cause mild abdominal
discomfort (cramps).
Senna is not recommended
for prolonged use as a laxative. (Long term use upsets water
and electrolyte balance).
Senna should not be taken
by those with intestinal obstruction (ileus) or undiagnosed
abdominal symptoms.
It is recommended that the
intake of sennosides should be no more than 15mg from a single
dose (2).
Senna may cause a harmful
reddening of the urine.
Pregnant and lactating women
should consult with a qualified health professional before
taking senna, due to a lack of safety data during this time.
Senna is not recommended for use by children.
NB The use of non-standardised
senna preparations should be avoided, since their effect will
be variable and unpredictable.
Interactions and Contra-Indications
Individuals with IBS and
IBD must exercise care when taking senna.
Senna may interfere with cardiac glycosides (such as digoxin).
Senna may potentiate anticoagulant therapy by reducing the
absorption of Vitamin K in the gut.
References
1. "Herbal Medicines",
CA Newall, LA Anderson, JD Phillipson, The Pharmaceutical
Press, 1996.
2. "Herbal Drugs and Phytopharmaceuticals", N Grainger
Bissett, Medpharm, 1994.
3. Eur J Pharmacol, 1996, 301; 1-3:137-142.
4. Eur J Pharmacol, 1997, 323;1:93-97.
5. J Pain Symptom Manage, 1998, 15; 1:1-7.
6. Pharmacology, 1993, 47 supply; 1:253-255. | 
