The present invention provides a composition for measuring the gastric-emptying function and a method for measuring the gastric-emptying function effectively usable in diagnosing dyspepsia. The present invention also provides a dyspepsia diagnostic agent, a method for diagnosing dyspepsia, and a method for measuring the treatment effect on a patient suffering from gastrointestinal disorders caused by insufficiencies in the gastric-emptying function (including a pharmacotherapy). One of the main features of the composition for measuring the gastric-emptying function of the present invention is that a pyrimidine compound, which is converted to a labeled CO 2 gas in the body and excreted in expired air, labeled with an isotope of C or O, is used as an active ingredient. The method of the present invention can be conducted by orally administering the composition to a subject, and measuring the amount or behavior of the labeled CO 2 excreted in expired air.本發明係有提供一種可用來有效地診斷消化管症候群之胃排出能測定用組成物以及胃排出能測定方法。本發明亦提供一種消化管症候群之診斷檢查藥以及消化管症候群之診斷檢查方法,對於具有以胃排出能不全為原因之胃腸問題患者測定其治療效果(包含藥物療法)之測定方法。本發明是使用在活體內可以變換成經標識CO2氣體而在呼氣排出之經同位素C或O中至少一者所標識的嘧啶化合物作為活性成份。排出能之測定則是經由將該組成物經口投藥給受測者,並測量受測者在呼氣中所排出之CO2氣體量或其行為來進行者。
