Pareira

Chondrodendron tomentosum

Uses

Pareira is popular for containing curare, the lethal poison used by the tribes in the Amazon basin on their arrow heads. Several famous explorers from Europe, counting Christopher Columbus and Sir Walter Raleigh came back from South America with numerous stories of how their men were killed by these 'evil' herbal products. In fact, curare is considered to be a silent killer that provided the native tribal populace with nearly a mystic advantage over their adversaries who were armed with guns. It is interesting to learn that in many countries, including the United States and Netherlands, the alkaloid tubocurarine extracted from pareira vine has been administered in the form of a deadly injection in euthanasia (mercy killing) and capital punishment. However, in a number of other countries, restrictions have been imposed on the use of tubocurarine. Till this day, the pareira vine is the sole recognized source of deltatubocurarine, an alkaloid that is yet to be synthesized by scientists, who first isolated this substance way back in 1935. Usually, d-tubocurarine is administered in small doses together with general anesthesia with a view to cause muscle paralysis. This alkaloid derived from pareira works to obstruct the transmission of nerve impulses to the receptor sites on skeletal muscles. In addition, d-tubocurarine is also employed in shock therapy as well as in setting broken bones. A number of people, including inhabitants of Brazil, regard pareira to be a diuretic as well as a stimulant for the uterus and use it for these purposes. In fact, the Brazilians also use d-tubocurarine for treating bites by poisonous snakes. Pareira is also a notorious herb because the poison depends on the consequence of its lethal offshoot that directly enters the bloodstream. However, internal consumption of pareira in the form of a remedy is practically safe provided you do not have any sores or cuts inside your mouth. The stems and roots of pareira have a bitter-sweet flavours and possess gentle laxative, stimulant as well as diuretic properties. In addition, this herb is also used to induce menstruation. The primary use of pareira is to alleviate chronic soreness of the tubules of the urinary system. As discussed above, people in Brazil also use pareira to treat poisonous snake bites. For this purpose, an infusion prepared from the roots of the vine is taken by mouth and, at the same time, the crushed leaves of this herb are applied topically on the site of the bites. People in Peru and neighbouring Brazil use the roots of this wooded vine to enhance urination, lower fever and induce menstruation. In addition, plants yielding curare are also employed for treating edema, inflammation of the testicles and kidney stones. It is applied topically on contusions and bruises. A homeopathic remedy is also prepared using this herb to cure enlarged prostate and urinary tract inflammation. Several early explorers, including Sir Walter Raleigh have reported that the Indian herbalists have been using the curare vine to treat various health conditions since the 1500s and much later it was introduced into the European herbal medicine. British herbalist Maude Grieve, who authored the book 'A Modern Herbal' (published for the first time in 1931), reported that these plants work in the form of an antiseptic for the bladder when the urinary passage is affected by chronic inflammation. In addition, this herb is also recommended for people suffering from edema, jaundice, rheumatism, vaginal discharges as well as gonorrhea. In fact, besides pareira, curare, which is used as a poison on arrow heads, is prepared from several other plants. In addition, different native Indian tribes inhabiting the Amazon basin use curare to prepare various recipes. Usually, the native Indians in Venezuela as well as those in the Guianas employ Strychnos plants in the form of the major ingredient, while the tribes in Ecuador, Brazil and Peru employ the curare vine called Chondrodendron tomentosum as the major constituent of the poisons prepared by them. In both instances, people generally combine the extracts of many dissimilar plants and often also add frog and snake venom to it to prepare the poisons. Several Indian tribes in South America, such as the Ketchwas in Ecuador, Sionas in Colombia, and the Lamistas in Peru employ curare vine to prepare their deadly poisons. They first crush the stems and roots of these plants and then cook them together with other different plants as well as venomous animals. These substances are boiled for prolonged periods (at times for as many as two days at a stretch) till the substances turn into a dark-colored paste or syrup. Subsequently, the final product is used to smear the drafts they use in their blow guns and their hunting arrow heads. In fact, these poisons are not genuine toxins - instead they are very strong muscle relaxants. Death due to curare poison is actually a result of asphyxia (stifling or respiratory arrest), as it makes the muscles to relax to such an extent that the muscles that regulate the lungs and diaphragm stop functioning. It is interesting to note that curare poison works only when the venom enters the bloodstream. Consuming curare poison and also consuming the meat of animals poisoned with curare does not have any toxic effect, since the stomach does not absorb this venom. Nevertheless, curare works wonderfully for the Indian hunters, as their prey is often located in an elevated position in the canopy - the action of the poison to relax the muscles thwart the animals from running away and it works to weaken or release their grasp on the tree branches, eventually making them fall on the ground. As soon as the poison enters the bloodstream of the prey, it starts acting instantly. However, death due to respiratory arrest or asphyxia may take some minutes in the case of birds as well as small animals, while it may take about 20 minutes or even more in the case of mammals, who generally have a larger body.

Constituents

Chemical analysis of the pareira stem has revealed that it is loaded with alkaloids. The alkaloid that is mainly responsible for the  muscle relaxing effects (the reason why it is used as a poison on the arrow heads) is known as d-tubocurarine.