Aristolochia contorta, also known as snakeroot and northern pipevine, is a perennial herbaceous plant that is native to Korea, Japan, and eastern China. It is a climbing vine that can grow up to 5 ft tall. The leaves are heart-shaped or triangular, and the flowers are yellow-green with purple veins. The plant contains the carcinogenic chemical compounds aristolochic acid and derivatives. It has been used medicinally in traditional Chinese medicine for centuries, but its use is now discouraged due to its health risks.