The present invention provides combinations of an antipsychotic drug and a tetracycline, particularly minocycline, for the treatment of psychotic disorders, particularly schizophrenia. The invention also provides formulations wherein the release of one or both of the antipsychotic drug and the tetracycline is modified. The invention also provides methods using the combined therapy for treatment of psychotic disorders, particularly schizophrenia, comprising an antipsychotic drug and a tetracycline.