Chuanmu is the dried woody stem of plants in the Menispermaceae family, such as Aristolochia debilis, Paraboea rufescens, or Sinomenium acutum. It has a cool nature and bitter taste, and enters the Heart, Small Intestine, and Bladder meridians. Chuanmu has the functions of clearing heat, promoting diuresis, and invigorating blood circulation. It is used to treat symptoms such as painful and difficult urination, cloudy urine, edema, chest distress and heat, throat obstruction and pain, generalized body pain, amenorrhea in women, and insufficient lactation. "Compendium of Materia Medica" states: "Chuanmu can clear the Heart, clear the Lungs, treat headaches, promote the function of the nine orifices, and can also relieve damp-heat, promote urination, regulate the Large Intestine, and treat generalized body pain." In the market, some counterfeit products labeled as Chuanmu are actually from the Menispermaceae family, but the term "Menispermaceae Chuanmu" has never been recorded in the ancient pharmacopoeia. Therefore, caution should be exercised when using it to avoid confusion.
Authentic Chuanmu
The dried woody stem is cylindrical and curved, with a length of 30-60 centimeters and a diameter of 1.2-2 centimeters. The surface is gray-brown, extremely rough with irregular cracks, and the nodes are not obvious, only the scars of lateral branches can be seen. The texture is hard and difficult to break. The cross-section is fibrous, with a thick yellow-brown bark and a yellow-white wood. It is densely filled with fine pore conduits and has a gray-yellow radial pattern. The center has small medullary tissue. It has a weak aroma and a slightly bitter and astringent taste.
Counterfeit Menispermaceae Chuanmu
The dried stem is cylindrical, similar in length and diameter to authentic Chuanmu. The surface is gray-yellow or brown, with slightly thicker nodes. The cut surface is yellow or yellow-white. The bark is thin, and the wood is wide with multiple layers of conduits arranged in a reticular pattern. The rays are light in color, and the medullary tissue is not obvious. The texture is solid and not easily broken. The cross-section of the bark is yellow-white and soft, while the wood is yellow, covered with small pores, and interspersed with yellow lines like a wheel. It has a weak aroma and an extremely bitter taste.
Modern pharmacological studies have shown that Chuanmu has significant diuretic effects. Its water decoction or infusion has varying degrees of inhibitory effects on various pathogenic fungi. On the other hand, counterfeit Menispermaceae Chuanmu does not belong to the same plant family as authentic Chuanmu, and it does not possess the various therapeutic effects of Chuanmu. Menispermaceae Chuanmu, which is the dried stem of Sinomenium acutum, contains the nephrotoxic component aristolochic acid. Excessive intake can cause aristolochic acid nephropathy, damaging the renal tubular epithelial cells and leading to interstitial fibrosis. Therefore, the use of Menispermaceae Chuanmu for medicinal purposes was officially banned in 2003 by the government. Careful identification is necessary to prevent the misuse of counterfeit products, which may not only delay treatment but also pose a risk of aristolochic acid nephropathy. Caution should be exercised when using it.
