title: Re: sildenafil adjunctive therapy to risperidone in the treatment of the negative symptoms of schizophrenia.
authors.forename: Gaurav N
authors.initials: GN
authors.lastname: Kaushik
mesh_terms: D014150:Antipsychotic Agents / Q000627:therapeutic use*; D006801:Humans; D058986:Phosphodiesterase 5 Inhibitors / Q000627:therapeutic use*; D010879:Piperazines / Q000627:therapeutic use*; D011687:Purines / Q000627:therapeutic use; D018967:Risperidone / Q000627:therapeutic use*; D012559:Schizophrenia / Q000188:drug therapy* / Q000503:physiopathology*; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000627:therapeutic use*
chemical_list: D014150:Antipsychotic Agents; D058986:Phosphodiesterase 5 Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate; D018967:Risperidone