Provided is an FTD- and TPI-containing oral pharmaceutical composition which can be orally administered and is stable even under high humidity conditions. This oral pharmaceutical composition contains alpha,alpha,alpha-trifluorothymidine and 5-chloro-6-(2-iminopyrrolidine-1-yl) methyl-2,4 (1H, 3H)-pyrimidine dione hydrochloride as the active ingredient, and contains, as an excipient, an additive having an 85% or greater critical relative humidity at 25 DEG C.本發明提供一種即便於高濕度條件下亦穩定且可經口投與之含有FTD及TPI之經口投與用醫藥組合物。本發明之經口投與用醫藥組合物含有α,α,α-三氟胸苷及5-氯-6-(2-亞胺基吡咯啶-1-基)甲基-2,4(1H,3H)-嘧啶二酮鹽酸鹽作為有效成分,含有25℃下之臨界相對濕度為85%以上之添加劑作為賦形劑。
