《本草》云∶马衔铁无毒。《日华子》云∶古旧铤者好，或作医工针。
按∶本草柔铁即熟铁，有毒，故用马衔则无毒。以马属午，属火，火克金，解铁毒，故
用以作针。古曰∶金针者，贵之也。又金为总名，铜、铁、金银之属皆是也。若用金针更佳
先将铁丝于火中 红，次截之，或二寸，或三寸，或五寸，长短不拘。次以蟾酥涂针上
，仍入火中微 ，不可令红，取起，照前涂酥 二次，至第三次，乘热插入腊肉皮之里、肉
之外，将后药先以水三碗煎沸，次入针肉在内，煮至水干，倾于水中，待冷，将针取出。于
黄土中插百余下，色明方佳，以去火毒，次以铜丝缠上，其针尖要磨圆，不可用尖 。
麝香（五分） 胆矾 石斛（各一钱） 穿山甲 当归尾 朱砂 没药 郁金 川芎 细辛
（各三钱） 甘草节 沉香（各五钱） 磁石（一两能引诸药入铁内）
又法∶用乌头、巴豆各一两，硫黄、麻黄各五钱，木鳖子、乌梅各十个，同针入水，用
瓷罐内煮一日，洗择之，再用止痛没药、乳香、当归、花乳石各半两，又如前水煮一日，取
出，用皂角水洗，再于犬肉内煮一日，仍用瓦屑打磨净端直，用松子油涂之，常近人气为妙
《素问》遗篇注云∶用圆利针、长针，未刺之时，先口内温针，暖而用之。又曰∶毫针
于人近体，暖针至温方刺。
按∶口体温针，欲针入经络，气得温而易行也。今或投针于热汤中，亦此意耳。口温与
体温微有不同，口温者针头虽热，而柄尚寒，不若着身温之，则针通身皆热矣。
《本草》记载：马嚼铁无毒。《日华子》记载：古旧的铁条较好，或者制作成医工使用的针具。
按语：本草中提到的柔铁即熟铁，是有毒的，所以使用马衔铁则没有毒性。因为马在五行中属午，对应火，火能克金（金属），从而化解铁的毒性，因此用马衔铁来制作针具。古人说“金针”，是表示珍贵之意。另外，“金”是总称，铜、铁、金银等都属于此类。如果使用真正的金针效果更佳。
先将铁丝在火中烧红，然后截断，长度可以是二寸、三寸或五寸，长短不拘。接着将蟾酥涂抹在针上，再次放入火中微微加热，不可烧红，取出后，照前法再涂一次蟾酥，如此共涂三次。第三次时，趁热将针插入腊肉皮的内部、肉的外部。先将药物用三碗水煎沸，然后将针和肉放入药水中，煮至水干，倒入水中冷却，取出针。在黄土中插戳百余下，直到颜色明亮才好，以去除火毒。然后用铜丝缠绕针柄，针尖要磨圆，不可尖锐。
药材及用量：麝香（五分）、胆矾、石斛（各一钱）、穿山甲、当归尾、朱砂、没药、郁金、川芎、细辛（各三钱）、甘草节、沉香（各五钱）、磁石（一两，能引导诸药进入铁内）。
另一种方法：使用乌头、巴豆各一两，硫黄、麻黄各五钱，木鳖子、乌梅各十个，与针一起放入水中，在瓷罐内煮一天，清洗挑选。再用止痛用的没药、乳香、当归、花乳石各半两，像前法一样水煮一天，取出，用皂角水洗，再放入犬肉中煮一天。最后用瓦屑打磨干净，使其端正笔直，涂上松子油，经常贴近人气（人体温度）为妙。
《素问》遗篇注记载：使用圆利针、长针时，在未针刺之前，先在口中温针，温暖后再使用。又说：毫针与人身体接触较多，暖针需达到温热程度才能针刺。
按语：用口体温针，是为了让针进入经络时，气因温暖而容易运行。现在有人将针投入热水中，也是这个意思。口温与体温略有不同，口温时针头虽热，但针柄尚寒，不如贴身温暖，这样针身通体皆热。
The *Bencao* (Materia Medica) states: Horse bit iron is non-toxic. The *Ri Hua Zi* (Daily Life of the Substances) states: Old iron bars are good, or they can be made into needles for medical practitioners.
Commentary: The soft iron mentioned in the Materia Medica refers to wrought iron, which is toxic; therefore, using horse bit iron renders it non-toxic. In the Five Elements theory, the Horse corresponds to Wu (noon) and Fire. Fire conquers Metal, thereby resolving the toxicity of iron; hence, horse bit iron is used to make needles. In ancient times, "gold needle" was said to indicate preciousness. Furthermore, "Metal" (Jin) is a general term encompassing copper, iron, gold, silver, etc. If genuine gold needles are used, the effect is even better.
First, heat the iron wire in fire until red-hot, then cut it. The length may be two cun, three cun, or five cun, with no fixed restriction. Next, apply Toad Venom (Chan Su) onto the needle, and place it back in the fire for slight heating, ensuring it does not become red-hot. Remove it, and apply Toad Venom again as before. Repeat this coating process three times. On the third occasion, while hot, insert the needle into the inner side of cured meat skin but outside the meat itself. First, boil three bowls of water with the following herbs, then place the needle and meat into the decoction. Boil until the water is dry, pour the contents into water to cool, and remove the needle. Insert the needle into yellow earth more than one hundred times until its color becomes bright, which is ideal, to eliminate fire toxicity. Then, wrap the handle with copper wire. The needle tip must be ground round, not sharp.
Herbs and Dosages: Moschus (She Xiang, 5 fen); Chalcanthite (Dan Fan); Dendrobii Caulis (Shi Hu), each 1 qian; Pangolin Scales (Chuan Shan Jia); Angelicae Sinensis Radix Cauda (Dang Gui Wei); Cinnabar (Zhu Sha); Myrrha (Mo Yao); Curcumae Aromatae Rhizoma (Yu Jin); Chuanxiong Rhizoma (Chuan Xiong); Asari Radix (Xi Xin), each 3 qian; Glycyrrhizae Radix et Rhizoma Articulus (Gan Cao Jie); Aquilariae Lignum Resinatum (Chen Xiang), each 5 qian; Magnetitum (Ci Shi, 1 liang, capable of guiding various herbs into the iron).
Another method: Use Aconiti Lateralis Radix Praeparata (Wu Tou) and Crotonis Fructus (Ba Dou), each 1 liang; Sulphur (Liu Huang) and Ephedrae Herba (Ma Huang), each 5 qian; Momordicae Semen (Mu Bie Zi) and Mume Fructus (Wu Mei), each 10 pieces. Place them in water with the needle, and boil in a porcelain jar for one day. Wash and select them. Then use Myrrha (Mo Yao) and Boswelliae Resina (Ru Xiang) for pain relief, along with Angelicae Sinensis Radix (Dang Gui) and Spodum (Hua Ru Shi), each half liang. Boil in water for one day as before. Remove, wash with Gleditsiae Sinensis Fructus (Zao Jiao) water, and then boil in dog meat for one day. Finally, polish clean and straighten with tile powder, coat with Pinus Massoniana Seed Oil (Song Zi You), and keep it close to human body heat, which is excellent.
The commentary on the lost chapters of the *Suwen* (Plain Questions) states: When using Yuanli Needles (Round-benefit Needles) and Chang Needles (Long Needles), warm the needle in the mouth before needling, and use it when warm. It also states: Since filiform needles (Hao Zhen) are in close contact with the patient's body, warm needles should reach a warm temperature before insertion.
Commentary: Warming the needle in the mouth aims to facilitate the smooth flow of Qi through the meridians once the needle enters, as Qi moves easily when warmed. Currently, some people immerse needles in hot water, which follows the same principle. There is a slight difference between mouth-warming and body-warming. With mouth-warming, although the needle head is hot, the handle remains cold. It is preferable to warm it against the body, so that the entire needle becomes hot.