Stabilized pharmaceutical compositions containing a calcium channel blocker

摘要

The present invention provides a pharmaceutical composition containing a calcium channel blocker of the following formula or a pharmacologically acceptable salt thereof and a pharmacologically acceptable alkaline material which is added to an extent such that an aqueous solution or dispersion solution of said pharmaceutical composition containing a calcium channel blocker has a pH of at least 8: [wherein R¹ represents an optionally substituted C₁-C₄ alkyl group, an amino group or a cyano group; R² represents an optionally substituted C₁-C₄ alkyl group, a substituted C₃-C₄ alkenyl group, or a substituted 4- to 6-membered cyclic amino group; R³ represents a substituted phenyl group; R⁴ represents an optionally substituted C₁-C₄ alkoxycarbonyl group, a 1,3,2-phosphorinan-2-yl group, or a 5,5-dimethyl-1,3,2-phosphorinan-2-yl group, R⁵ represents a C₁-C₄ alkyl group].