[Problem] To provide an aqueous suspension comprising a glucocorticosteroid compound as an active ingredient. More particularly, to provide a practically usable medicinal composition that comprises a glucocorticosteroid compound as an active ingredient. [Solution] An aqueous suspension agent characterized by comprising nanoparticles of a glucocorticosteroid compound and a dispersion stabilizing agent； the aqueous suspension agent wherein the average particle diameter of the nanoparticles is 300 nm or less and the D90 particle diameter thereof is 450 nm or less； and a medicinal composition for parenteral administration, an injection, eye drops or ear drops comprising the aforesaid aqueous suspension, more particularly, eye drops for treating or preventing an inflammatory eye disease, or ear drops for treating or preventing an inflammatory ear disease.
