Purpose: I studied mentions of urine in the Hippocratic Collection.
Materials and methods: I collected mentions of urine in the Hippocratic Collection (Roeb, Otsuki and Kon editions) to compare descriptions between the Kos and Knidos schools.
Results: Urine was mentioned in 396 passages. Descriptions by Kos, Knidos, and unspecified schools accounted for 355 (90%), 24 (6%), and 17 (4%), respectively. Of the 396, 386 (98%) referred to urinary findings, 9 (2%) to significance of urine in diagnosis, 3 to treatment according to urinary findings, and 4 to vapor baths with urine used by the Knidos school. Findings in urine were mentioned in 39 categories in total as thick or thin, clear or turbid, "concocted" or "unconcocted", watery, colorless or "good colored", bloody, clotted, purulent, and others. Colors of urine were mentioned in 27. Black ([symbol: see text]) and white ([symbol: see text]) were observed frequently, followed by red ([symbol: see text]) and yellow or yellowish ([symbol: see text]), and others. Urinary sediment was mentioned in 30 as smooth, uniform, cloudy, branny, or others. White urine tended to be thick, and black urine to be thin. Urine was "good" when white ([symbol: see text]) or yellow ([symbol: see text]), and the sediment was white, smooth and uniform: it was "bad" when black and thin, fetid, watery, or with branny.
Conclusions: Urinary findings were mentioned in the Hippocratic Collection, most frequently by the Kos school, and findings varied. Color descriptions by Hippocrates differed from those in present-day Japanese. White ([symbol: see text]) urine may be pale yellow, since ([symbol: see text]) actually means neither white nor colorless, but pale-yellow as white ([symbol: see text]) port-wine. Thick white ([symbol: see text]) and thick yellow ([symbol: see text]) urine may represent yellow and yellow-brown concentrated urine of healthy persons. Black ([symbol: see text]) urine may indicate gross hematuria, as red ([symbol: see text]) port-wine and thin blackish ([symbol: see text]) urine may indicate hematuria together with dilute urine, presumably as in renal failure.