Because of containing aristolochic acid, Aristolochia fangchi herb (Guang Fang Ji) was no longer used in pharmaceutical production and ever since stephania tetrandra (Han Fang Ji) becomes its main substitute. This notice was issued by China’s State Food and Drug Administration (SFDA) on September 30, 2004. This change could be dated back to the year of 1993. That year Lancet reported that Vanherweghem and others initially found two cases of young women suffering from rapidly progressive renal interstitial fibrosis were closely associated with diet pills containing aristolochia Fangchi and Hou Po (Magnolia Bark). To 1995, more than 80 similar cases had been discovered at the same region in Europe. And later this condition was officially named as Chinese herbs nephropathy (CHN). So, what is aristolochia fangchi found in? How this herb is used in TCM to reduce the toxicity? Though this herb is seldom used in herbal remedies now, it is worth going it over and prevents the tragedy happening again.
What is Aristolochia fangchi?
It refers to the dry root of Aristolochia fangchi Y.C.Wu ex L.D. Chou et S.M. Hwang, a plant belonging to Aristolochiaceae. Main habitats are hillsides and open forests. Medicinally it is primarily produced from Guangdong and Guangxi in China. Other common names are Aristolochia root, radix Aristolochiae fangji, and more. For better medicinal properties, it is preferably harvested during autumn and winter. Next, wash, cut into sections, cut the bigger ones in half lengthways, and dry in the sun.
Its plant is a perennial climbing vine, up to 3 to 4 meters. Roots are thick, cylindrical, and with well-developed cork. Stems are slender, less branching, taupe or brown-black, and densely covered with brown hair. Leaves are alternate. Petiole is 1 to 4cm in length and densely covered with brown hair. Blades are round or ovate-oblong, 3 to 17cm long, 2 to 6cm wide, and with acuminate or obtuse apex, cordate or rounded base, and entire margin. Flowers grow solitarily in leaf axils. Pedicels are about 1 to 2cm long and brown haired. Perianth is tubular, about 5cm, purple, and with yellow spots. Capsule comes with many seeds. It usually flowers during May to June and fruits from July to September.
Main chemical constituents of Aristolochia root
It mainly contains aristolochic acid I, aristololactam, allantoin, magnoflorine, and β-sitosterol. And on average 0.13% to 0.15% aristolochic acid I is found in the species from Zhaoqing Guangdong, 0.21% to 0.24% from Qingyuan Guangdong, and 0.7% from Guangxi.
Aristolochia root properties in Chinese herbal remedies
In Traditional Chinese medicine (TCM), it is believed as bitter and acrid in flavor and cold in nature. And it covers meridians of bladder and lung. Essential functions are dispelling wind to relieve pain, clearing heat, and using diuretic of hydragogue to alleviate water retention. Basic aristolochia fangchi uses and indications are damp-heat bodily pain, wind-damp pain or numbness, lower extremity edema, difficult urination, and beriberi induced pain and swelling. Recommended dosage is from 4.5 to 9 grams in decoction.
Aristolochia fangchi side effects and contraindications
Medicinally other Fang Ji herbs include Cocculus orbiculatus (L.) DC. (Mu Fang Ji) and Stephania tetrandra S. Moore (Fen Fang Ji). As mentioned above, the main component of Aristolochia root is aristolochic acid (AA). Studies show that AA is toxic to rabbits, goats, rats, mice and humans and has a strong carcinogenic effect in rodents. And pharmacokinetic studies also indicated that AA could accumulate in human body and the renal damage was basically proportional to the amount of intake. CHN is mainly characterized by tubular necrosis. On the basis of combined histological and laboratory studies, German scholar Mengs observed AA renal toxicity in different doses and confirmed that its histopathologic feature was renal tubular epithelial cell necrosis. And functionally increased serum creatinine and blood urea nitrogen was simultaneously accompanied with the rising of UGLU (urine glucose), urinary protein, Urinary N-acetyl-β-(D)-glucosaminidase (NAG), urinary excretion of γ-glutamyltransferase (GGT), and urinary malate dehydrogenase.
In China ancient herbalists has long been aware of this herb’s side effects and contraindications. And it needs to be used strictly under the guidance of professional TCM practitioners based on the diagnosis. If abusing it against the principle of compatibility, the adverse reactions can be expected soon. And now once again this lesson was learned in the hard way.
In summary, this issue on Aristolochia fangchi is a valuable wake-up call to any TCM practitioner. They should learn at least three things from this lesson.
1. Be a professional TCM doctor and avoid using medicine blindly. By doing so, it can prevent accidental iatrogenic damage;
2. Prohibit unreasonable compatibility. The medication should be based on reliable clinical and experimental facts, especially in the combination of Chinese medicine and western medicine;
3. Go into the mechanism of renal toxicity and clinically provide scientific reference for rational drug use.