Sustained release medicinal compositions

摘要

The present invention relates to sustained-release pharmaceutical compositions for ionic pharmaceutically active substances containing ionic compounds having opposite charges to those of ionic prostanoic acid derivatives and increasing hydrophobicity of the active substances. More specifically, the invention relates to sustained-release pharmaceutical compositions comprising the ionic prostanoic acid derivatives and the ionic compounds having opposite charges to those of the prostanoic acid derivatives and increasing hydrophobicity of these derivatives that contain hydrophobic groups in the molecule thereof. The pharmaceutical composition of the invention can exhibit excellent sustained release effect of the ionic prostanoic acid derivatives, irrespective of water solubility possessed by the ionic prostanoic acid derivatives.