When the dissolution test is carried out according to the dissolution test method described in b) the dissolution test method described in the Japanese Pharmacopoeia 16th edition, General Test Method (a) containing a physiologically active ingredient exhibiting bioactivity in a trace amount, a) oral disintegration time is within 30 seconds ( Test solution: water 900 mL, 37 C.), dissolution rate of the physiologically active ingredient at 15 minutes is 80% by mass or more, and c) Dissolution test is carried out according to the dissolution test method described in the Japanese Pharmacopoeia 16th edition, General Test Method Orally disintegrating tablet having a dissolution rate of the physiologically active ingredient in the test solution of 5% by mass or less at the time required for oral disintegration (test solution: water 900 mL, 37 C.). With this orally disintegrating tablet, the segregation of content is suppressed, the sensation of ingestion is improved, and the physiologically active ingredient (drug) which has a low content (trace amount) and a problem of ingestion is problematic has good drug dissolution properties.微量で生理活性を示す生理活性成分を含有し、a)口腔内崩壊時間が30秒以内であり、b)日局16版、一般試験法に記載の溶出試験法に従い溶出試験を実施したとき(試験液:水900mL、37℃)、15分での生理活性成分の溶出率が80質量%以上であり、かつc)日局16版、一般試験法に記載の溶出試験法に従い溶出試験を実施したとき(試験液:水900mL、37℃)、口腔内崩壊に要する時間の時点で試験液中の生理活性成分の溶出率が5質量%以下である口腔内崩壊錠剤。この口腔内崩壊錠剤は、低含量(微量)でかつ服用感が問題となる生理活性成分(薬物)について、含量偏析が抑制され、服用感が改善され、かつ良好な薬物溶出性を有する。
