麻山藥，薯(shu)蕷(yu)科、薯(shu)蕷(yu)屬植物，纏(chan)繞草質藤(teng)本。塊莖長(chang)圓柱形，垂直生(sheng)長(chang)，身長(chang)可(ke)達1米多，斷(duan)面干(gan)時呈白色。莖通常帶紫紅色，右旋，無(wu)毛。多生(sheng)長(chang)于陰涼處的山區(qu)，可(ke)以(yi)入藥，口感很好(hao)。

　　纏繞草質藤本(ben)。塊莖長圓(yuan)(yuan)柱形(xing)(xing)(xing)(xing)(xing)，垂直(zhi)(zhi)生(sheng)(sheng)(sheng)長，長可(ke)達1米多(duo)，斷面(mian)干時(shi)(shi)白色(se)(se)。莖通常(chang)(chang)帶紫(zi)紅(hong)色(se)(se)，右旋(xuan)，無(wu)毛。單葉(xie)，在莖下部(bu)的互生(sheng)(sheng)(sheng)，中(zhong)(zhong)部(bu)以上的對生(sheng)(sheng)(sheng)，很少3葉(xie)輪生(sheng)(sheng)(sheng)；葉(xie)片變異大，卵(luan)狀(zhuang)(zhuang)三(san)角形(xing)(xing)(xing)(xing)(xing)至(zhi)寬(kuan)(kuan)卵(luan)形(xing)(xing)(xing)(xing)(xing)或(huo)戟形(xing)(xing)(xing)(xing)(xing)，長3-9 (-16) 厘(li)(li)米，寬(kuan)(kuan)2-7 (-14) 厘(li)(li)米，頂端漸尖(jian)，基部(bu)深心(xin)形(xing)(xing)(xing)(xing)(xing)、寬(kuan)(kuan)心(xin)形(xing)(xing)(xing)(xing)(xing)或(huo)近截形(xing)(xing)(xing)(xing)(xing)，邊緣常(chang)(chang)3淺裂至(zhi)3深裂，中(zhong)(zhong)裂片卵(luan)狀(zhuang)(zhuang)橢圓(yuan)(yuan)形(xing)(xing)(xing)(xing)(xing)至(zhi)披針形(xing)(xing)(xing)(xing)(xing)，側裂片耳狀(zhuang)(zhuang)，圓(yuan)(yuan)形(xing)(xing)(xing)(xing)(xing)、近方形(xing)(xing)(xing)(xing)(xing)至(zhi)長圓(yuan)(yuan)形(xing)(xing)(xing)(xing)(xing)；幼苗時(shi)(shi)一般葉(xie)片為寬(kuan)(kuan)卵(luan)形(xing)(xing)(xing)(xing)(xing)或(huo)卵(luan)圓(yuan)(yuan)形(xing)(xing)(xing)(xing)(xing)，基部(bu)深心(xin)形(xing)(xing)(xing)(xing)(xing)。葉(xie)腋(ye)內常(chang)(chang)有(you)(you)珠芽(ya)。雌雄異株。雄花(hua)(hua)(hua)序為穗(sui)狀(zhuang)(zhuang)花(hua)(hua)(hua)序，長2-8厘(li)(li)米，近直(zhi)(zhi)立(li)，2-8個著(zhu)生(sheng)(sheng)(sheng)于葉(xie)腋(ye)，偶(ou)而(er)呈(cheng)圓(yuan)(yuan)錐(zhui)狀(zhuang)(zhuang)排列(lie)；花(hua)(hua)(hua)序軸明(ming)顯地呈(cheng)“之”字狀(zhuang)(zhuang)曲折(zhe)；苞(bao)片和花(hua)(hua)(hua)被片有(you)(you)紫(zi)褐色(se)(se)斑點；雄花(hua)(hua)(hua)的外(wai)輪花(hua)(hua)(hua)被片為寬(kuan)(kuan)卵(luan)形(xing)(xing)(xing)(xing)(xing)，內輪卵(luan)形(xing)(xing)(xing)(xing)(xing)，較小；雄蕊6。雌花(hua)(hua)(hua)序為穗(sui)狀(zhuang)(zhuang)花(hua)(hua)(hua)序，1-3個著(zhu)生(sheng)(sheng)(sheng)于葉(xie)腋(ye)。蒴果(guo)不反折(zhe)，三(san)棱(leng)(leng)狀(zhuang)(zhuang)扁圓(yuan)(yuan)形(xing)(xing)(xing)(xing)(xing)或(huo)三(san)棱(leng)(leng)狀(zhuang)(zhuang)圓(yuan)(yuan)形(xing)(xing)(xing)(xing)(xing)，長1.2-2厘(li)(li)米，寬(kuan)(kuan)1.5-3厘(li)(li)米，外(wai)面(mian)有(you)(you)白粉(fen)；種子著(zhu)生(sheng)(sheng)(sheng)于每室中(zhong)(zhong)軸中(zhong)(zhong)部(bu)，四(si)周(zhou)有(you)(you)膜質翅。花(hua)(hua)(hua)期6-9月，果(guo)期7-11月。

　　山(shan)藥味甘，性(xing)平；歸脾、肺(fei)、腎經；具有(you)健脾補肺(fei)、益(yi)(yi)胃補腎、固腎益(yi)(yi)精、聰耳(er)明目、助五臟、強(qiang)筋骨、長志(zhi)安神、延(yan)年益(yi)(yi)壽的功(gong)(gong)效。山(shan)藥含有(you)淀粉酶(mei)(mei)、多酚氧化(hua)酶(mei)(mei)等物質，有(you)利于脾胃消化(hua)吸收功(gong)(gong)能(neng)。《藥品化(hua)義》中記(ji)載：“山(shan)藥，溫補而(er)(er)不(bu)驟(zou)，微香(xiang)而(er)(er)不(bu)燥，循循有(you)調肺(fei)之功(gong)(gong)，治肺(fei)虛久嗽，何其穩當。因(yin)其味甘氣香(xiang)，用(yong)之助脾，治脾虛腹瀉，怠惰嗜臥(wo)，四肢困(kun)倦。又取其甘則補陽，以能(neng)補中益(yi)(yi)氣，溫養肌肉，為(wei)肺(fei)脾二臟要藥。”