Stephania

• Check which plant is in the bottle: 'fang ji' can mean a kidney-poisoning plant. The name fang ji covers more than one root. The kidney-toxic plant Aristolochia fangchi (guang fang ji) is sometimes substituted for, or mixed into, Stephania tetrandra (han fang ji) because the roots look alike. Aristolochic acid in the substitute has caused kidney failure and urinary tract cancer. If you cannot confirm the exact species, plant part and supplier, do not use it. Human case report ^{16 12 8}
• The Belgian slimming-clinic cases. In Brussels in the early 1990s, young women on a slimming regimen that listed Stephania tetrandra developed rapidly progressive kidney scarring (Chinese-herb nephropathy). The first 1993 report did not find the cause. Later work found a manufacturing error had put Aristolochia fangchi in the pills in place of Stephania. Of 39 patients who had their kidneys and ureters removed as a precaution, 18 (46 percent) had urothelial cancer, and all tissue samples carried aristolochic-acid DNA marks. Human case report ^{14 8 10}
• Pure Stephania tetrandra is not shown to contain aristolochic acid. Analyses of authenticated S. tetrandra found no aristolochic acid, and fang ji from Aristolochia fangchi is the one that does. So the danger is substitution and adulteration, not the true plant. But you cannot tell by eye, and the 1993 report noted that the capsules taken had unexpected alkaloid profiles. Laboratory ^{2 16 14}
• Kidney damage from aristolochic acid cannot be reversed. A 2023 review says there is no effective treatment to delay or reverse aristolochic acid nephropathy. Cases still appear, and the true number is probably underestimated. Cancer can appear years later, so people exposed may need long-term urinary screening. Narrative review ²²
• Tetrandrine itself has liver and lung toxicity signals. Even the true plant alkaloid is a drug with toxicity. In animals and lab cells tetrandrine damaged the liver and lungs, partly through CYP3A enzymes. In a study of treated silicosis patients, liver-function abnormalities and facial pigmentation were reported as mild. Do not treat it as a mild tea. Animal and lab ^{3 6 13 21}
• Medicine interactions are possible. Tetrandrine is broken down by CYP3A4 and CYP3A5 and blocks calcium channels, so interactions with CYP3A drugs, blood-pressure medicines and heart-rhythm medicines are plausible. They have not been tested in people. Laboratory ^{6 15 4}
• Pregnancy and breastfeeding: avoid. No safety data in pregnancy, breastfeeding or children were found. Because aristolochic acid is a carcinogen and kidney poison and tetrandrine is a potent drug with toxicity signals, avoid all fang ji products. Expert opinion ^{22 6}

LiverTox was not read. In animals tetrandrine caused liver injury by blocking glutathione S-transferase enzymes. In silicosis patients on tetrandrine, mild liver-function abnormalities were reported. We found no detailed case report of serious liver injury in the abstracts we read. ^{3 21}

How often. No reliable frequency is available.

Monitoring. Anyone taking tetrandrine as a prescribed drug should have liver tests as their doctor directs. Stop and seek care for yellow skin or eyes, dark urine, or pale stools.

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This is a safety connection. It is not evidence that Stephania supports liver health.

Summary. Two separate hazards. First, aristolochic acid from a substituted plant (kidney failure, urinary tract cancer). Second, tetrandrine itself, which can injure liver and lung in animals and cells.

Animal. A single high injected dose of tetrandrine caused lung bleeding in mice; liver injury was shown in an animal model via enzyme blockade.

Human doses studied. Silicosis and arthritis trials used the purified drug under medical care; this page gives no doses. Their abstracts report mild adverse effects.

High dose or long term signals. Liver-function abnormalities and facial pigmentation after prolonged treatment in one cohort; long-term safety data are sparse.

Overdose response. Not reported in the abstracts read.

Genotoxicity. Not assessed in sources read for tetrandrine. Aristolochic acid is a recognised carcinogen forming DNA adducts.

Toxic plant parts. The root is the part used. Aristolochia fangchi (the substitute) root is the toxic one. Other parts of Stephania were not assessed.

Substitution and adulteration with Aristolochia fangchi is the central quality hazard for anything sold as fang ji.

Name confusion. Fangji can refer to the root of Aristolochia fangchi, Stephania tetrandra or Cocculus trilobus. Only the Aristolochia contains aristolochic acid. Allowed substitutions in practice raise the exposure risk. ¹⁶

Look-alike roots. Roots are morphologically similar and adulteration is documented. Lab methods can tell them apart and spot as little as 10 percent adulteration. ^{12 2}

Ongoing exposure. Aristolochic acid exposure persists; sporadic cases continue after regional bans. ²²

• Passing much less urine, swelling of legs or face, unusual tiredness, nausea or itching (possible kidney failure).
• Blood in the urine, or pain in the side or back that does not settle.
• Yellow skin or eyes, dark urine or pale stools (possible liver injury).
• New cough, chest pain or breathlessness (possible lung injury).
• Fainting, a very slow or irregular heartbeat, or very low blood pressure.
• Swelling of the lips, tongue or throat, wheezing or trouble breathing (possible allergy).

Stop the supplement and contact a clinician or emergency service. In the US, Poison Control is 1-800-222-1222.