Guang Fang Ji

Aristolochia fangchi is a woody, deciduous climbing vine of the Aristolochiaceae, native to subtropical broadleaf forests of southern China (notably Guangdong and Guangxi) and northern Vietnam. The slender twining stems may reach 5–10 m. Alternate, long-petioled leaves are oblong-ovate to narrowly cordate, 8–18 cm long, glabrous and dull green above with paler pubescence beneath. The bilaterally symmetrical pipe-shaped flowers, characteristic of the genus, are yellow-green flushed with purple-brown markings. The cylindrical, longitudinally six-ribbed capsule splits at maturity. The medicinal organ is the dried root, cylindrical or somewhat tortuous, with a thick yellow-brown bark and pale yellow woody centre. The species contains nephrotoxic aristolochic acids and is the documented causative agent of the Belgian 'Chinese-herb nephropathy' outbreak; it is now banned or withdrawn from medicinal use in most jurisdictions.