【方歌】蛇眼疔在甲旁生，甲后名为蛇背疔，蛀节疔生中节骨，
蛇腹指内鱼肚形，泥鳅疽生遍指肿，牵引肘臂热焮疼，
看生何指分经络，总由脏腑火毒成。
【注】此证有五：如蛇眼疔生于指甲两旁，形于豆粒色紫，半
含半露，硬似铁钉；蛇背疔生于指甲根后，形如半枣，
色赤胖肿；蛀节疔又名蛇节疔，生于中节，绕指俱肿，
其色或黄或紫；蛇腹疔又名鱼肚疔，生于指中节前面，
肿如鱼肚，色赤疼痛；泥鳅疽一指通肿，色紫，形如泥
鳅，焮热痛连肘臂。初起俱宜服蟾酥丸汗之，外敷雄黄
散，次服仙方活便饮，脓熟开之，贴琥珀膏煨脓生肌；
虚不能敛者补之。但此五证，总不外乎火毒凝结而成。
至于属何经脏，临证看生何指以辨之。
手指经络，各详注首卷。
方剂：蟾酥丸（见疔疮门）
雄黄散（见蛇头疔）
仙方活命饮（见肿疡门）
琥珀膏（见头部发际疮内）
【方歌】代指每生指甲身，先肿焮热痛应心，轻溃微脓重脱甲，
经脉血热是其因。
【注】此证生于手指甲身内，由经脉血热凝结成。初起先肿焮
热，疼痛应心，宜用甘草、朴硝各五钱，熬水浸洗即瘥
。痛仍不止，三、四日后，指甲背面上微透一点黄白色
，此系内脓已成，但无门溃出，急用线针在指甲身就脓
近处捻一小孔，脓方得出，随手捏尽余脓，用黄连膏贴
之易愈。或失治，或过敷凉药，以致肌肉寒凝，脓毒浸
淫好肉，爪甲溃空，必然脱落，用琥珀膏贴之，一两月
即愈。
方剂：黄连膏（见鼻部鼻疮）
琥珀膏（见头部发际疮内）
【方歌】蛇眼疔生长在指甲旁边，指甲后方生长的称为蛇背疔，蛀节疔生长在中节指骨处，
蛇腹疔在手指内侧肿胀如鱼肚形状，泥鳅疽表现为整个手指肿胀，疼痛牵连肘部和手臂且伴有灼热感，
根据发生的具体手指来辨别所属经络，总归是由脏腑火毒所致。
【注】此病证有五种：如蛇眼疔生于指甲两旁，形状像豆粒，颜色紫暗，半露出甲外，质地坚硬似铁钉；蛇背疔生于指甲根部后方，形状像半个枣子，
颜色红赤且肿胀；蛀节疔又名蛇节疔，生于中指节，环绕手指全部肿胀，
其颜色或黄或紫；蛇腹疔又名鱼肚疔，生于手指中节的前面，
肿胀如同鱼肚，颜色红赤且疼痛；泥鳅疽表现为一个手指整体肿胀，颜色紫暗，形状像泥鳅，灼热疼痛牵连至肘臂。初起时都适宜服用蟾酥丸以发汗解表，外用雄黄散敷贴，随后服用仙方活命饮，脓液成熟后切开排脓，贴敷琥珀膏以煨脓生肌；
体质虚弱不能收敛疮口者予以补益治疗。但这五种病证，总不外乎是火毒凝结而成。
至于属于哪条经络和脏腑，临证时需观察发生在哪个手指来进行辨别。
手指的经络分布，详见本书首卷注释。
方剂：蟾酥丸（见疔疮门）
雄黄散（见蛇头疔）
仙方活命饮（见肿疡门）
琥珀膏（见头部发际疮内）
【方歌】代指每发生于指甲内部，起初肿胀灼热，疼痛剧烈直达心脏，轻微者溃破流出少量脓液，严重者指甲脱落，
经脉血热是其病因。
【注】此病证生于手指指甲内部，由经脉血热凝结所致。初起先出现肿胀灼热，
疼痛剧烈直达心脏，适宜用甘草、朴硝各五钱，熬水浸泡清洗即可痊愈。
如果疼痛仍然不止，三、四日后，指甲背面微透出一小点黄白色，
这是内部脓液已经形成，但缺乏出口排出，急需在线针于指甲靠近脓液处捻出一个小小孔洞，脓液才能流出，随即捏尽剩余脓液，用黄连膏贴敷则容易愈合。或者因失治，或过度敷用凉药，导致肌肉寒凝，脓毒侵蚀好肉，爪甲溃烂中空，必然脱落，此时用琥珀膏贴敷，一两个月即可痊愈。
方剂：黄连膏（见鼻部鼻疮）
琥珀膏（见头部发际疮内）
[Prescription Verse] Sheyan Ding (Snake-Eye Carbuncle) arises beside the nail, while that behind the nail is named Shebei Ding (Snake-Back Carbuncle); Zhujie Ding (Woodworm-Joint Carbuncle) occurs at the middle phalanx bone, and Shefu Ding (Snake-Belly Carbuncle) presents with a fish-belly swelling on the palmar side of the finger. Niqiu Ju (Loach Ulcer) involves diffuse swelling of the entire finger, with heat, inflammation, and pain radiating to the elbow and arm. One must identify the meridian based on the affected finger; ultimately, these conditions are caused by Fire-Toxin accumulating in the Zang-Fu organs.
[Annotation] There are five types of this condition: For instance, Sheyan Ding arises on both sides of the nail, resembling a bean in size, with a purple color, partially exposed, and hard like an iron nail; Shebei Ding arises behind the nail root, shaped like half a jujube, with redness and swelling; Zhujie Ding, also known as Shejie Ding, occurs at the middle joint, causing circumferential swelling of the finger, with colors varying from yellow to purple; Shefu Ding, also known as Yudu Ding, appears on the anterior aspect of the middle finger joint, swelling like a fish belly, with redness and pain; Niqiu Ju presents with uniform swelling of one finger, purple in color, shaped like a loach, accompanied by burning heat and pain radiating to the elbow and arm. In the initial stage, it is appropriate to administer Chansu Wan (Toad Venom Pill) to induce sweating, apply Xionghuang San (Realgar Powder) externally, followed by taking Xianfang Huoming Yin (Immortal Recipe for Saving Lives Decoction). Once pus matures, incise and drain, then apply Hupo Gao (Amber Ointment) to promote pus formation and tissue regeneration; for those with deficiency unable to close the wound, tonify them. However, all five conditions essentially result from the coagulation of Fire-Toxin. Regarding which meridian or Zang-Fu organ is involved, differentiation is made clinically by observing which finger is affected. The meridians of the fingers are detailed in the annotations of the first volume.
Formulas: Chansu Wan (see section on Ding Chuang/Carbuncles), Xionghuang San (see section on Shetou Ding/Snake-Head Carbuncle), Xianfang Huoming Yin (see section on Zhongyang/Ulcers), Hupo Gao (see section on Head Scalp Sores).
[Prescription Verse] Daizhi (Subungual Abscess) typically occurs within the nail bed, initially presenting with swelling, burning heat, and pain severe enough to reach the heart. Mild cases may ulcerate with slight pus discharge, while severe cases result in nail shedding. The etiology is Blood-Heat in the meridians.
[Annotation] This condition arises within the fingernail, caused by the coagulation of Blood-Heat in the meridians. Initially, there is swelling and burning heat, with pain radiating to the heart. It is suitable to use Gancao (Licorice Root) and Puxiao (Mirabilite) each 5 qian, boiled in water for soaking and washing, which will lead to recovery. If pain persists, after three to four days, a small yellowish-white spot may appear on the dorsal surface of the nail, indicating that internal pus has formed but lacks an exit. Urgently use a thread needle to prick a small hole near the pus on the nail plate to allow drainage, then squeeze out residual pus, and apply Huanglian Gao (Coptis Ointment) for easy healing. Alternatively, if treatment is neglected or cold-natured medicines are over-applied, leading to cold coagulation of muscles and erosion of healthy tissue by pus-toxin, the nail will become hollow and inevitably shed. In such cases, apply Hupo Gao (Amber Ointment), and recovery will occur within one to two months.
Formulas: Huanglian Gao (see section on Nasal Sores), Hupo Gao (see section on Head Scalp Sores).