Fang Ji Huang Qi Tang (Stephania and Astragalus Decoction) fáng jǐ huáng qí tāng · 防己黄芪汤

Safety. Fang Ji Huang Qi Tang pairs two things that are usually kept apart: a herb that drains water and a herb that is given to people who are tired and depleted. Huang qi raises and secures the exterior; fang ji drains damp; bai zhu, ginger, jujube and liquorice hold the middle. The pattern it is written for is specific and slightly counter-intuitive - a person who is damp and heavy and who is also sweating and cannot tolerate a draught. Classical reading explains that as surface deficiency: the exterior is not holding, so sweating and wind-aversion come together with retention of fluid. Whether one finds that explanation satisfying or not, it is what the formula is aimed at, and this entry reports it as a description of the tradition rather than as a claim about physiology. One ingredient carries a safety issue that outranks everything else on this page. Fang ji is a name covering more than one plant. Han fang ji, also called fen fang ji, is Stephania tetrandra of the Menispermaceae family and does not contain aristolochic acid. Guang fang ji is Aristolochia fangchi, a member of the birthwort family, and does contain it. The two were traded under the same name, and the consequences of that are documented: in the nineteen-nineties a Belgian slimming clinic that used an aristolochia species in place of the intended herb produced a cluster of rapidly progressive kidney failure, and a substantial share of those patients later developed urothelial cancer. Aristolochic acid causes interstitial nephropathy that does not reverse, and it is a carcinogen with cumulative exposure and no established safe threshold. Chinese authorities withdrew the aristolochia species from medicinal use in the early two-thousands. Any modern preparation of this formula must use Stephania root. If a source, a supplier or a label says fang ji without saying which fang ji, that is not a detail. The remaining cautions are smaller but real. Liquorice in sustained amounts produces a syndrome that looks like excess aldosterone - raised blood pressure, low potassium, oedema - which is an awkward property in a formula given for oedema, and it interacts with diuretics, digoxin and antihypertensive medicines. Astragalus is immunologically active, and while it is widely used and generally well tolerated, that activity is a reason for caution in people on immunosuppressive treatment or with autoimmune disease. Oedema is also a sign with a differential: heart failure, nephrotic syndrome, cirrhosis, venous insufficiency, deep vein thrombosis, hypothyroidism and several common drugs - calcium channel blockers, NSAIDs, corticosteroids - all produce it, and unilateral leg swelling raises the question of a clot. New or worsening breathlessness with oedema belongs to an emergency department, not to a decoction. Weight loss and joint symptoms are modern applications that have been attached to this formula; this library records the traditional indication and does not assert those modern ones.