Dysphania ambrosioides

Let’s conclude the medicinal plant diversity series with a species originating in Mesoamerica. Today’s photographs are courtesy of Forest & Kim Starr, the photographers behind many of the images on the Hawaiian Ecosystems at Risk project. These images, plus many more, can be found on the photographs page for Dysphania ambrosioides (here labeled under a synonym, Chenopodium ambrosioides).

As implied above, Dysphania ambrosioides has readily spread (in some places, invasive) from its native southern North America to northern South America range to tropical and warm-temperate regions around the world (modern distribution in northern North America). Common names abound for the species, ranging from American wormseed to paico (Peru) and epazote (Latin America) to erva de Santa Maria (Brazil).

Dysphania ambrosioides has the quality of being both a spice and a traditional medicinal herb. Gernot Katzer’s excellent Spice Pages has the details on epazote as a leafy herb, including its common names in 32 languages and its use in Mexican cuisine for foods such as refried beans (added due to its antiflatulent properties).

On the medicinal side–and in addition to its use as an antiflatulent–wormseed or wormwort was long-used globally as an antihelminthic, a drug that helps expel intestinal worms. The most medicinally active compound in Dysphania ambrosioides is ascaridole, present in its oil. In particular, there is a cultivated type of Dysphania ambrosioides known as Chenopodium ambrosioides var.? subsp.? anthelminticum (or sometimes Chenopodium anthelminticum) that is grown for its high concentrations of the chemical in the seed oil (the taxonomy is very uncertain here, not sure if the cultivated type is botanical or horticultural in origin). Use of Dysphania ambrosioides as an antihelminthic, however, declined significantly in the 1930s as less toxic medicines for treatment were developed, retreating from mainstream use in Europe, North America and South America to only being used significantly as a traditional medicine in its native Mesoamerica.

Cornell University’s Medicinal Plants for Livestock: Dysphania ambrosioides gives an excellent account of the history of the species in cultivation and discusses the extreme toxicity of the oil (2 teaspoons of the oil can kill or adversely effect an adult sheep). It also warns “The dose that causes adverse effects is very close to the dose that is supposed to be efficacious. Therefore, extreme caution should be used when treating an animal with this plant or the oil made from the plant.”. It should also be noted that in high concentrations, it is used as an insecticide.

Few references mention this, but the species has also received a recent examination as a candidate drug for cancer treatment: see Efferth, T. et al. 2002. Activity of ascaridol from the anthelmintic herb Chenopodium anthelminticum L. against sensitive and multidrug-resistant tumor cells. Anticancer Res. 22(6C):4221-4.

Dysphania ambrosioides
Dysphania ambrosioides

5 responses to “Dysphania ambrosioides”

  1. Lynne

    Epazote is common here in the desert SW of the United States but I never knew it had so many other uses. Interesting writeup — thanks!

  2. kathryn corbett

    Living in southern Mexico for a number of years, I found this to be one of the most commonly sold fresh herbs in the open markets. One does indeed develop a taste for it–it’s delicious with black beans, very aromatic. The epazote plant in my garden was just killed to the ground by recent temps in the high 20s here on California’s north coast. Sob.

  3. Jonathan Knisely

    It’s a bit surprising to me that the antiflatulent properties of this herb have not been more specifically (and scientifically) evaluated. My understanding of the cause of flatulence is the delivery of undigested polysaccharides (complex sugars) to bacteria in the colon, which then metabolize them, producing gas. How would this herb help prevent the development of flatulence? By inhibiting microbial ability to utilize this foodsource? By assisting with breakdown of the sugars so that they can be absorbed in the small intestine? I’d think there’d be a product to be put on the drugstore shelf waiting to be discovered.

  4. Eric Simpson

    I’ve seen this plant all of my life here in San Diego County (pulled some from my yard just yesterday), and have long wondered if it were native or not (though based on where/how it appears in the landscape, I judged it “not”). Now that you’ve ID’ed it for me, I checked the Jepson site, and they say it’s non-native but naturalized in CA. Glad to know that my inclination to treat it as a weed was correct. Interesting about the medicinal properties, and doubly glad that I treat it as a weed now that I know how toxic it is!

  5. Patrick Cullinan

    Epazote is sold in the supermarkets here in Brooklyn, NY. It even grows in the cracks in the sidewalks! I never use it — cilantro is my potherb of choice when cooking latin-style.

Leave a Reply