Erva Tostão is a vigorous growing weedy vine found in many tropical and warm-climate countries from Brzil to India. The roots of Erva Tostão have held an important place in herbal medicine in both Brazil and India for many years. In Brazil, Erva Tostão is considered 'a plant medicine of great importance, extraordinarily beneficial in the treatment of liver disorders.' It is most often used as a tea or thick boiled decoction. It is employed in Brazilian herbal medicine as a chologogue (stimulating the flow of bile from the liver) and diuretic, for all types of liver disorders including jaundice and hepatitis, for gallbladder pain and stones, urinary tract and renal disorders and calculi, and for cystitis. Erva Tostão is called Purnarnava or Punarnava in India where it has a long history of use by indigenous and tribal people, and in Aruyvedic or natural/herbal medicine in India. There, the roots are employed for many purposes including liver, gallbladder, kidney, renal and urinary disorders. The worldwide use of Erva Tostão roots for various liver complaints and disorders were validated when researchers demonstrated in 1980 and again in 1991 that a root extract provided antihepatotoxic properties in animals; protecting the liver from numerous introduced toxins. In other clinical studies with animals, a root extract demonstrated smooth muscle and skeletal muscle stimulant activity in frogs and guinea pigs; hypotensive actions in dogs as well as in-vitro hypotensive actions; antispasmodic actions in frogs and guinea pigs; antiamebic actions in rats; and hemostatic or antihemorrhaging properties in monkeys with IUDs. The traditional use of Erva Tostão for convulsions and epilepsy was verified by scientists in two studies demonstrating that a root extract provided anti-convulsant action in mice. In vitro testing of Erva Tostão root extract show that has antibacterial properties including against gonorrhea, antinematodal properties and antiviral actions against several viral plant pathogens. The diuretic action of Erva Tostão has been studied and validated by scientists in several studies which help to explain its long history of use in various kidney and urinary conditions. Researchers showed in the mid 1950's that low dosages (10mg/kg to 300mg/kg) produced strong diuretic effects while higher dosages (>300mg/kg) produced the opposite effect, reducing urine output. Other researchers who followed, verified these diuretic and anti-diuretic properties as well as the beneficial kidney and renal effects of Erva Tostão roots in animals and humans. Research indicates that a root extract can increase urine output by as much as 100% in a 24 hour period at dosages as low as 10mg per kilogram of body weight.