A method is described for the production of dosage forms, which comprise a solid dispersion of a microcrystalline active substance, in which a thermoplastic polymer with a glass transition temperature Tg of at least 40° C. is melted and an active substance is dissolved homogeneously in the melt； crystallization of the active substance is initiated in the mass obtained； and the mass is cooled. Crystallization of the active substance can be initiated by adding a nonsolvent, seed crystals of the active substance or a derivatization reagent. In addition, crystallization can be initiated by holding the mass for a sufficient length of time at a temperature that is below the temperature at which the active substance is completely soluble in the mass.
