In order to provide the medical field with a single formulation comprising a modified release portion containing mirabegron or a pharmaceutically acceptable salt thereof and an immediate release portion containing solifenacin or a pharmaceutically acceptable salt thereof, (1) a single formulation having dissolution rates of both drugs similar to those of the current single drug formulations is provided, and (2) a single formulation having maximum percentages of dissolution of both drugs of 90% or more, and having a bioavailability equivalent to those of the current single drug formulations. Further, in order to provide a single formulation, (3) a single formulation having good productivity whereby failures in tabletting are reduced, and having good storage stability whereby the coloration of the immediate release portion is suppressed is provided. The pharmaceutical composition for oral administration of the present invention contains (1) a modified release portion comprising mirabegron or a pharmaceutically acceptable salt thereof, and (2) an immediate release portion comprising solifenacin or a pharmaceutically acceptable salt thereof, and calcium stearate.
