The "Treatise on Cold-Damage Disease" considers the presence or absence of difficulty in urination as an important marker for differentiating between water retention and blood accumulation. Water retention is a disease of the qi aspect, where the transformation of qi is impaired, leading to difficulty in urination. Blood accumulation, on the other hand, is a disease of the blood aspect and does not affect the function of qi transformation, hence urination remains normal. Personally, I believe this only describes the general rule and does not account for all variations. If static blood obstructs and affects the function of qi transformation, not only can difficulty in urination be observed, but also symptoms of swelling and fullness. From a clinical perspective, conditions such as rheumatic heart disease, liver cirrhosis with ascites, and renal failure can all present with difficulty in urination, ascites, or swelling and fullness. These conditions often exhibit varying degrees of static blood manifestations. If one only addresses the symptom of difficulty in urination from the qi aspect, the expected results may not be achieved. However, sometimes significant efficacy can be obtained by using blood-stasis-breaking herbs, which is thought-provoking. I have personally used leech powder to treat "wind-heart" cases presenting with epigastric stuffiness, ascites, and difficulty in urination, as well as "lung-heart" cases with facial edema, panting, foot swelling, and scanty urine, with relatively good results, which can serve as evidence.

Zhang Xi-chun's "Li Chong Wan" (leech, raw Astragalus Root, raw Sparganium Rhizome, raw Zedoary Rhizome, Chinese Angelica, Anemarrhena, raw Peach Kernel) has shown relatively significant efficacy for all zang-fu organ abdominal masses and women with blood stasis amenorrhea or postpartum lochiorrhea forming abdominal masses. It can also be used for colicky heart pain in coronary heart disease. My personal experience is that for cases characterized by qi stagnation and blood stasis, meridian spasms, and poor blood circulation leading to colicky heart pain, or even myocardial infarction, with obvious ecchymosis on the tongue and lips, adding 1 gram of leech powder (encapsulated, taken in two doses) to the usual blood-invigorating and stasis-resolving, qi-regulating, and yang-promoting formulas often yields excellent results. Additionally, it can have varying degrees of efficacy for conditions such as post-splenectomy thrombocytosis in portal hypertension and esophageal cancer, but it may cause fulminant diarrhea, which stops upon discontinuation. It should be used cautiously in debilitated individuals.