Senna Hebecarpa

American senna,Wild Senna, Maryland Senna, Indian Senna

Botany 

American senna, or Senna hebecarpa, is a member of the pea family ( Fabaceae) and is native to most of the eastern half of the United States as well as Ontario, Canada1. Interestingly, the plant is either threatened or endangered in several states in the Northeast including Vermont, New Hampshire, and Massachusetts1. The plant often grows to heights of two to four feet, and produces dense clusters of small yellow blooms in mid to late summer. The flowers themselves are cup-shaped disks radiating from a central darker bulb1. Insects and other animals attracted to the flower include butterflies, hummingbirds, and bumblebees2. Leaves of the plant are grayish-green and found with 5-10 pairs of leaflets per compound leaf3. Senna prefers to grow in the moist, neutral soil of open woods, stream banks, and disturbed areas in sunny zones or with partial shade; it often forms vegetative colonies by spreading underground rhizomes of fibrous roots2,4. Special care must be considered when growing this plant due to a potentially dangerous sensitivity to the toxins produced by the plant that can cause poisonings or fatal illness when ingested in large quantities.

Chemistry

Active components of the senna plant, found in the pods and leaves, include anthraquinone glycosides and sennasides which both produce the laxative effect, as well as carbohydrate sugars, flavonols, salicylic acid, chrysophanic acid, and mannitol5

Fun Fact

History

The first known medicinal use of Senna leaves was as a cathartic tea by Arabian physicians as early as 9th century A.D. Traditional Arabic and European medicines used dried senna leaves and pods to make a strong laxative to treat constipation3. The plant is still commonly used for the same purpose today. 

Uses/Pharmacology

Senna works as a stimulant laxative by acting on the intestinal wall to increase muscle contractions and move along the stool mass through the intestines.

Dosing/Recipes

One particular recipe for a tea infusion recommends using 0.5-3.0 grams of dried senna leaf infused in hot water for 10-15 minutes or in cold water for 10-12 hours5. However, many conditions are contraindicated for this treatment including bowel obstruction, abdominal pain of unknown cause, any intestinal inflammatory condition, hemorrhoids, and in children under 12 years of age5. Another recipe uses 4-12 dried pods steeped in warm water for 6-12 hours. When made into a tincture, the recommended dose is 2-7ml three times a day until symptoms are gone6.

If raw plant extracts or infusions are unavailable or undesirable, there is also the option of using standardized dosage forms available in all major drugstores. Senna extracts are still used today and available as nonprescription OTC stimulant laxative powders, liquids, tablets, capsules, and suppositories to treat constipation

Contraindications/Interactions/Adverse Reactions

When using laxatives, it is always important to read and follow package directions to prevent misuse of the medication. Dehydration is a serious side effect, so anyone taking laxatives should remember to drink plenty of fluids.

References Cited

1. Senna hebecarpa. United States Department of Agriculture: Plants Database. Accessed 19 Feb 2012. Available online from < http://plants.usda.gov/java/profile?symbol=SEHE3>.

2. Senna hebecarpa. Lady Bird Johnson Wildflower Center. The University of Texas at Austin, 2012. Accessed 9 March 2012. Available online from <http://www.wildflower.org/plants/result.php?id_plant=SEHE3>.

3. Hilty, John. Senna hebecarpa. Illinois Wildflowers, 2012. Accessed Available online from <http://www.illinoiswildflowers.info/savanna/plants/wild_senna.htm>.

4. Cassia hebecarpa. Native Wildflowers and Prairie Plants. Ion Exchange, Inc., 2012. Accessed 14 April 20112. Available online from <http://ionxchange.com/products/TEUCRIUM-CANADENSE-%7C-Germander.html>.

5. McGuffin M, Hobbs C, Upton R, Goldberg A. American Herbal Products Association’s Botanical Safety Handbook. CRC Press, LLC; 1997, pp106-107.

6. Hoffman, David. The Complete Illustrated Hollistic Herbal: A Safe and Practical Guide to Making and Using Herbal Remedies, pp143.