夫医首重望闻，次贵问切，人皆知之矣。至于痧，而望闻有所未明，问切有所未尽，医其可以已乎？吾观世有暗痧
而人不识，往往多误，则曷不取痧筋以验之。盖针锋所刺，不过锋尖微微入肉，有痧毒者，方有紫黑血流；若无痧毒者，
其锋尖虽刺，点滴全无。故痧有痧筋可辨，亦如别病之有别症可辨也。然则痧筋所现者，青紫之色，所原者，乃本于血
中之有其毒欤。夫血中有毒，既无可消，自宜知放，放有不尽，则宜刮、宜药，审寒凉而权轻重，借草木以挽凶危。凡
以驱夫痧毒之所留滞者，而救其大命焉尔。奈何有不信痧者，徒受夫痧症之实祸，而甘心于自毙乎。
痧若紧者，只在顷刻，慢者，或期至十日半月而死，或期至一月二月而死，甚有期至三四月而死，此诚痧之慢矣。
而余谓必须速治者，毋乃忧人之太过乎？而不知其非也。夫痧之致人于死者，虽有如是之久，而其痧毒蔓延于肠胃、经
络间者，正多凶险之处，即如痧毒滞结于身之或左或右，或上或下、或里或中或表，既有若是之滞结者，必不尤然若是
之滞结而已也。将且在内者，先坏脏腑，在中者，先损经络，在表者，先溃肌肉。虽未即毙，而其难治之形必然先见，
若一不治，便成死症。慢痧之可畏也如是，安可以死日之慢，而不速为之早治乎。
中医诊疗首重望诊和闻诊，其次重视问诊和切诊，这是众所周知的道理。然而对于痧症而言，仅靠望诊和闻诊有时难以明辨，仅靠问诊和切诊有时也难以穷尽病机，医生难道就可以因此停止诊治吗？我观察世间存在隐蔽的“暗痧”而人们无法识别，往往导致误治，那么为什么不通过观察“痧筋”来验证呢？因为针尖刺入皮肤，不过微微进入皮肉之中，如果有痧毒的人，就会有紫黑色的血液流出；如果没有痧毒的人，虽然针尖刺入，却点滴血也无。所以痧症可以通过痧筋来辨别，也如同其他疾病通过其他症状来辨别一样。然而痧筋所呈现的是青紫色，其根源在于血液中蕴含有毒素吗？既然血液中的毒素已经形成且无法单纯依靠药物消除，自然应当知道采用放血疗法，如果放血不能排尽毒素，则适宜采用刮痧或药物治疗，审察病性的寒凉程度以权衡治疗的轻重，借助草木药性来挽回危急局面。这一切都是为了驱除滞留体内的痧毒，从而挽救患者的生命罢了。为何有人不相信痧症的存在，白白遭受痧症带来的真实祸害，而甘心于自我死亡呢？
痧症发作急迫的，可能在顷刻之间致死；发作缓慢的，有的期限长达十天半月而死，有的长达一个月两个月而死，甚至有长达三四月才死的，这确实是属于慢痧了。而我主张必须迅速治疗，难道是过于担忧了吗？其实并非如此。导致患者死亡的痧症，虽然病程看似漫长，但其痧毒在肠胃、经络间蔓延扩散时，正隐藏着许多凶险之处。就像痧毒停滞结聚在身体的左侧或右侧、上方或下方、体内或体表中部等位置，既然已经有了这样的滞结，必然不会仅仅保持这种滞结状态而已。它将进而导致内部的脏腑先被破坏，中间的经络先受损伤，体表的肌肉先溃烂。虽然患者尚未立即死亡，但那种难以救治的征象必然先期出现，一旦不予治疗，就会成为死症。慢痧的可畏惧之处正是如此，怎么能因为死亡日期尚远，就不迅速及早进行治疗呢？
In medicine, observation (Wang) and listening/smelling (Wen) are prioritized, followed by inquiry (Wen) and palpation/pulse diagnosis (Qie); this is well known to all. However, regarding Sha syndrome (a condition characterized by toxic heat or stasis manifesting as skin changes), observation and listening may not be fully illuminating, and inquiry and palpation may not exhaustively reveal the pathology; can a physician simply cease treatment? I observe that in the world there are cases of "hidden Sha" (An Sha) that go unrecognized, often leading to misdiagnosis. Therefore, why not use the examination of "Sha Jin" (visible subcutaneous veins indicating Sha toxin) to verify it? When the needle tip pierces the flesh slightly, only those with Sha toxin will have dark purple-black blood flow out; for those without Sha toxin, even if pierced by the needle tip, not a single drop of blood appears. Thus, Sha syndrome can be distinguished by Sha Jin, just as other diseases are distinguished by their specific symptoms. The color presented by Sha Jin is cyanotic-purple; its origin lies in the presence of toxins within the blood, does it not? Since these toxins in the blood cannot be eliminated solely by medication, one should naturally know to employ bloodletting. If bloodletting does not completely expel the toxin, then scraping (Gua Sha) or herbal medicine is appropriate. One must assess the cold-cool nature of the pathogen to weigh the severity of treatment, utilizing the properties of herbs to rescue from critical danger. All this serves to drive out the retained Sha toxin and save the patient's life. Why do some people disbelieve in Sha syndrome, suffering the real calamity of Sha manifestations, and resign themselves to death?
If Sha attacks rapidly, death may occur within moments; if it is slow, death may come in ten days or half a month, or even in one or two months, and sometimes up to three or four months; this is indeed what is called "Slow Sha." Yet I insist on immediate treatment; is this excessive worry? No, it is not. Although the course leading to death from Sha may seem prolonged, the Sha toxin spreading through the intestines, stomach, meridians, and collaterals harbors many perilous situations. For instance, if Sha toxin stagnates and knots in the body—whether on the left or right, upper or lower, interior or exterior—it will not remain stagnant in that state alone. It will proceed to damage the internal Zang-Fu organs first, injure the meridians and collaterals in the middle, and ulcerate the muscles on the surface first. Although death does not occur immediately, the signs of incurability will inevitably appear beforehand. If left untreated, it becomes a fatal case. Such is the terror of Slow Sha. How can one refrain from early and rapid treatment merely because the date of death seems distant?