Simaruba is a medium sized to large tree that grows up to 15 to 25 meters in height with a trunk 50-80 cm in diameter. It produces bright green leaves 20 to 50 cm in length and a small red fruits. It is indigenous to the Amazon Rainforest and other tropical areas in Mexico, Cuba, Haiti, Jamaica and Central America.

The leaves and bark of Simaruba have a long history of use as natural medicine in the tropics where it grows. It was first imported into France from Guyana in 1713 as a remedy for dysentery. The country suffered an epidemic from 1718 to 1725 and Simaruba was one of the few effective treatments.⁽¹⁾ French explorers "discovered" this effective remedy when they found that the indigenous tribes in the Guyana rainforest used Simaruba bark as an effective treatment for malaria and dysentery much as they still do today.⁽²⁾ Other indigenous tribes throughout the South American Rainforest use Simaruba bark for fevers, malaria, dysentery, as a hemostat to stop bleeding, and a tonic.^{(3, 4)}

Simaruba has a long history in herbal medicine in many countries as well. In Cuba it is called Gavilan and an infusion of the leaves or bark is considered astringent, digestive, anthelmintic and an emmenagogue; used for diarrhea, dysentery, malaria, colitis, and used externally for wounds and sores.⁽⁵⁾ In Belize, the tree is named Negrito or "Dysentery Bark" and the bark and sometimes the root is boiled in water to yield a powerful astringent and tonic used for dysentery, diarrhea, stomach and bowel disorders, hemorrhages, internal bleeding and used to wash skin sores.⁽⁶⁾ In Brazil, it is employed much in the same way against fevers, diarrhea, dysentery, intestinal parasites, dyspepsia as well as anemia.⁽⁷⁾ In Brazil, Simaruba bark tea is highly recommended as the best and most effective natural remedy against chronic and acute dysentery.⁽⁸⁾

Simaruba bark's uses for dysentery caused by amebic infections were reported in 1918. A military hospital in England demonstrated that the bark tea had antiamebic activity in humans reporting the bark tea was an effective treatment for amebic dysentery.⁽⁹⁾ Scientists first looked at Simaruba's antimalarial properties in 1947 when they determined a water extract of the bark as well as the root demonstrated strong activity against the malaria-causing organism, Plasmodium gallinaceum in chickens.⁽¹⁰⁾ The study showed that small doses of only 1 mg of bark extract to 1 kilo of body weight exhibited strong antimalarial activity.⁽¹⁰⁾ In 1962, researchers found that the seeds of Simaruba showed active antiamebic activities in humans⁽¹¹⁾ and the National Cancer Institute verified that Simaruba seed was 91.8% effective against intestinal amoebiasis in humans in a 1976 study.⁽¹²⁾ In much of the early studies, the plant constituents found in the bark, root and leaves of Simaruba attributed with the anti-malarial and antiamebic properties were a group of quassinoids, similar to those found in Quinine Bark. In 1978, scientists discovered a new quassinoid in Simaruba which significantly inhibited the growth of lymphocytic leukemia in vitro.⁽¹³⁾ A similar quassinoid called glaucarubinone is found in Simaruba as well as other plants in the Simaroubaceae family which has demonstrated antileukemic and cytotoxic activities in other studies.⁽¹⁴⁾