PROBLEM TO BE SOLVED: To provide medicines useful for blood purification in patients with kidney disease, as well as medicines useful for suppression of progression of chronic kidney disease (severe chronic kidney disease), treatment and prevention of uremic symptoms, and delayed introduction of dialysis.SOLUTION: The present invention discloses a pharmaceutical composition for accelerating excretion of a uremic substance containing an alkalizing agent, preferably an alkali metal citrate salt, to the outside of the body. The uremic substance is selected from indoxyl sulfate, p-cresyl sulfate, phenylacetyl acetyl L glutamine, hippuric acid and argininosuccinate.EFFECT: It is possible to preliminarily judge whether uremia substances are discharged to the outside the body in mammals, whether uremic substances are discharged outside the body and whether progression of chronic kidney disease can be suppressed or not.SELECTED DRAWING: NoneCOPYRIGHT: (C)2019,JPO&INPIT【課題】腎臓病患者における血液浄化に有用な医薬、慢性腎臓病の進行(慢性腎臓病の重症化)の抑制、尿毒症症状の治療及び予防、透析導入の遅延に有用な医薬の提供。【解決手段】アルカリ性化剤、好ましくはクエン酸アルカリ金属塩を含む尿毒症物質の体外への排泄促進用医薬組成物。尿毒症物質がインドキシル硫酸、p-クレジル硫酸、フェニルアセチルアセチルLグルタミン、馬尿酸及びアルギニノコハク酸から選択される、医薬組成物。【効果】哺乳動物において尿毒症物質の体への排出、尿毒症物質が体外に排出されるか否か、慢性腎臓病の進行が抑制できているか否かの予備的判断が可能。【選択図】なし