Huang Qi Gui Zhi Wu Wu Tang (Astragalus and Cinnamon Five-Substance Decoction) huáng qí guì zhī wǔ wù tāng · 黄芪桂枝五物汤

Safety. Huang Qi Gui Zhi Wu Wu Tang is a well-known formula with a well-known pedigree, and the pedigree is the quickest way into it: take gui zhi tang, remove the liquorice, add huang qi, and increase the fresh ginger. That is all. Five ingredients, and the change is the argument. Removing gan cao takes away the sweet, slowing, harmonising centre; adding huang qi puts the emphasis on raising and on the surface; more ginger pushes outward. What the source text points it at is blood impediment - a body that feels numb or insensitive, described there as being like wind impediment but without the pain of it. The traditional reading is that the surface is not being nourished and the channels are not being moved, and that the remedy is to warm and move rather than to drain. Whether one accepts that account or reads it as a pre-modern description of a circulation problem, the formula is coherent, and the way it is derived from its parent is worth understanding as a piece of reasoning. Numbness is a symptom, and it is one of the symptoms where the differential has a time-critical branch. Diabetic peripheral neuropathy, cervical radiculopathy and myelopathy, carpal tunnel syndrome, vitamin B12 deficiency, hypothyroidism, alcohol and chemotherapy neuropathy, Guillain-Barre syndrome, and multiple sclerosis all present with numbness or altered sensation. Most are assessed electively. Three are not: a cord or cauda equina lesion with numbness around the saddle and new bladder or bowel difficulty, Guillain-Barre with ascending weakness, and - by far the most common - sudden one-sided numbness or weakness with slurred speech or facial droop, which is stroke and belongs to the emergency system, because the treatments that change the outcome are bounded by the clock. Traditional blood impediment covers numbness; it does not sort it, and this library will not pretend otherwise. The cautions are the familiar ones from this family of herbs, plus one specific to huang qi. Astragalus is immunologically active. That activity is why it is used, and it is also why people on immunosuppressive medicines, people with autoimmune disease and transplant recipients have a reason to raise it with their own clinician before taking it; the theoretical risk of stimulating the immune system in the wrong direction is not a trivial one even though the herb is widely used and generally well tolerated. Gui zhi contains coumarin, for which European food-safety authorities have set a tolerable daily intake on the grounds of liver toxicity in susceptible people, and cassia cinnamon contains considerably more of it than Ceylon cinnamon. Large amounts of fresh ginger are well tolerated in food and the antiplatelet concern is weak and largely theoretical. Shao yao in modern practice is usually white peony root, not red. The modern application of this formula to diabetic peripheral neuropathy is something this entry records as a modern use and does not assess.