The present invention is to provide a composition for internal use which improves solubility in intestines and is excellent in bioavailability. More specifically, the present invention relates to a composition for internal use which contains (A) roperamide hydrochloride, and at least one organic acid selected from a group consisting of (B) malic acid, tartaric acid, adipic acid, fumaric acid, maleic acid, malonic acid, and citric acid.本發明提供一種改善腸內的溶解性、生物學上的利用能力優異的內服組成物。一種內服組成物，含有：（A）洛哌丁胺鹽酸鹽；以及（B）選自蘋果酸、酒石酸、己二酸、富馬酸、馬來酸、丙二酸及檸檬酸中的一種以上的有機酸。
