What is curare?

   Curare is any of various poisons prepared from the leaves, roots, and bark of several South American plants. Crude curare is a gummy brown substance that was once widely used as an arrow poison by the Indians of Brazil, Ecuador, and British Guiana.
   Curare contains several poisonous substances that prevent the nerves from sending impulses to the muscles of the body, thus causing paralysis. Since the muscles that control the lungs are affected by curare, the drug may cause death by suffocation.
   In medicine very small amounts of highly purified curare are used during surgery to relax the muscles. The drug is also used in the treatment of certain muscular diseases.