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Senna

What is senna?

Senna is a shrub whose leaves and fruits are used to make medicine. Senna is an over-the-counter laxative that can be used to treat constipation and to empty the digestive tract before diagnostic examinations such as colonoscopies. Senna is also used for irritable bowel syndrome, hemorrhoids and to aid weight loss. The fruits of senna appear to be better tolerated than senna leaves.

How effective is senna?

Senna is likely to be effective in the treatment of constipation. Taking senna orally for short-term treatment of constipation has been shown to be effective. Senna is also suitable for the treatment of children aged 2 years and older, although in children aged 3 to 15 years, mineral oil and a drug called lactulose may be more effective. In older people, a combination of senna and psyllium is more effective than lactulose for treating persistent constipation. Senna may be effective for preparing the digestive tract before a colonoscopy. Oral ingestion of senna may be effective in cleansing the bowel before a colonoscopy. However, sodium phosphate or polyethylene glycol are more effective alternatives. There is currently insufficient scientific data to evaluate the effectiveness of senna for hemorrhoids and irritable bowel syndrome, as well as for weight loss support. Further scientific research is needed to evaluate the effectiveness of Senna in these applications.

How does Senna work?

Senna contains chemicals called sennosides. Sennosides irritate the intestinal mucosa, resulting in a laxative effect.

Are there any safety concerns?

Senna is probably safe and harmless for most adults and children over the age of two for short-term use. However, senna can cause some side effects, including stomach discomfort, cramping and diarrhea.

Senna should not be used for more than two weeks. Prolonged use may interfere with normal bowel function and cause dependence on laxatives. In addition, prolonged use may disrupt the electrolyte balance in the blood, which can lead to impaired heart function, muscle weakness, liver damage and other adverse effects.

Precautions and warnings

  • Pregnancy and lactation: Senna may be safe during pregnancy and lactation if used for short periods. It may not be safe when used long-term or at higher doses. Prolonged regular use or the use of high dosages has been associated with serious side effects such as laxative dependence and liver damage.

Although small amounts of senna may pass into breast milk, this does not appear to be a problem for breastfed infants. As long as the mother uses senna in the recommended amounts, senna does not cause changes in the frequency and consistency of bowel movements in breastfed infants.

  • Electrolyte imbalance, potassium deficiency: Excessive use of senna can aggravate these conditions.
  • Dehydration, diarrhea or loose stools: Senna should not be used by people suffering from dehydration, diarrhea or loose stools as it may aggravate these conditions.
  • Digestive tract conditions: Senna should not be used by people suffering from abdominal pain, digestive tract blockages, Crohn's disease, ulcerative colitis, appendicitis, inflammation of the stomach, anal prolapse or hemorrhoids.
  • Heart disease: Senna can cause electrolyte imbalance and aggravate heart disease.

Interactions with medications

Care should be taken when combining Senna with the following medications:

Diuretics

Senna is a laxative. Some laxatives can lower potassium levels in the body. Diuretics can also lower potassium levels, which means that combining Senna with diuretics could lower potassium levels in the body too much.

Are there any interactions with medicinal herbs or supplements?

Horsetail

There are concerns that the use of senna in combination with horsetail could increase the risk of excessive drops in blood potassium levels.

Licorice

There are concerns that the use of senna in combination with licorice could increase the risk of an excessive drop in blood potassium levels.

Medicinal herbs that act as stimulant laxatives

There are concerns that taking senna in combination with medicinal herbs that act as stimulant laxatives may increase the risk of potassium levels dropping too low. Such medicinal herbs include blue aloe, iris, buckthorn, walnut bark, buckthorn bark, castor oil, bitter melon, gum bark extract, jalapeño root, mannar bark extract, Himalayan mayapple root, rhubarb root, senna leaves and husks, and spearmint root.

Are there any interactions with food?

There are no known interactions with food.

Dosage

The following dosages have been scientifically investigated:

Oral intake:

  • For constipation in adults and children aged 12 years and over. The dosage usually used is 17 mg per day. No more than 35 mg per day should be used.
  • For constipation in children under 12 years of age: 8.5 mg per day with an increase if necessary to the minimum amount needed to achieve one bowel movement per day.
  • For constipation in the elderly: 17 mg per day.
  • For constipation after pregnancy: 28 mg divided into two doses.

References

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