The problem to be solved by the present invention is to provide a medicine which is excellent in the treatment of type 2 diabetes, diabetic complications or impaired glucose tolerance. The present invention provides a medicine characterized in that a compound represented by the following general formula (I), a salt thereof, or a solvate thereof, and at least one kind of other diabetic medicine:(wherein R1, R2, R3 and R4 are each a hydrogen atom, a trifluoromethyl group or a C1-3 alkyl group) .