PREPARATIONS FOR ORAL ADMINISTRATION

摘要

The present invention provides a preparation for oral administration containing a medicinal substance having cGMP-specific phosphodiesterase inhibitory activity and showing decrease of solubility in the neutral and alkaline regions, wherein an acidic substance is compounded promote the dissolution of the medicinal substance in digestive tract and thus the efficacy can be expressed at the early stage after administration, and which preparation is useful in treatment of erectile dysfunction.