1. A method for preventing agglomeration of particles of an active ingredient in a suspension； where the suspension contains the active ingredient and silicone oil and / or a silicone oil derivative in a dispersion medium； the active ingredient is at least one substance selected from the group consisting of aripiprazole and a compound represented by structural formula (II): the active ingredient is in the form of particles having an average primary particle size of 0.1 μm or more and less than 200 μm； the method comprising mixing the active ingredient a solvent with silicone oil and / or a silicone oil derivative in a dispersion medium, such that the silicone oil and / or silicone oil derivative is contained in an amount of from 0.001 to 0.2 parts by weight relative to 100 parts by weight of the active ingredient contained in the suspension. 2. A method for preventing agglomeration of particles of an active ingredient in a suspension according to claim 1, wherein the active ingredient is aripiprazole. 3. A method for preventing agglomeration of particles of an active ingredient in a suspension according to claim 1, wherein the active ingredient is a compound represented by structural formula (II): 4. A suspension comprising an active ingredient and a silicone oil and / or a silicone oil derivative in a dispersion medium； where the active ingredient is at least one substance selected from the group consisting of aripiprazole and a compound represented by structural formula (II): wherein the active ingredient is in the form of particles and has an average primary particle size of 0.1 microns or more and less than 200 microns； silicone oil and / or silicone derivative1. Способ для предотвращения агломерации частиц активного ингредиента в суспензии；где суспензия содержит активный ингредиент и силиконовое масло и/или производное силиконового масла в дисперсионной среде；активным ингредиентом является, по меньшей мере, одно вещество, выбираемое из группы, состоящей из арип
