A 27-year-old, Caucasian, male patient, diagnosed with substance-induced psychotic disorder, was hospitalized due to exacerbation of psychotic symptoms despite clozapine dose of 150 mg/day for two years. His family reported exacerbation of obsessive-compulsive symptoms, such as contamination obsessions and frequent handwashing, for 3 months. Clozapine and norclozapine plasma levels were lower than therapuetic level on admission. a 15-mg/day aripiprazole was added on and clozapine dose increased to 200 mg/day. At the end of the first week, aripiprazole dose was increased to 30 mg/day. Plasma clozapine and norclozapine levels were found to be higher than therapeutic level with a clozapine dose of 200 mg/day, and clozapine dose decreased to 100 mg/day. The clozapine and aripiprazole doses, plasma drug levels, and the clinical rating scale scores are given in Table \n. At the end of the fourth week, during discharge, his scores of PANSS was 46 (159 at admission), and YBOCS was 10 (30 at admission).
Mr. L, a 48-year-old man with a diagnosis of residual schizophrenia [] treated for many years with clozapine 500 mg/d was admitted because of the worsening of his anxiety. The clinical scores and the trough plasma concentrations of clozapine and norclozapine were: CGI : 4; total PANSS: 88; positive: 20/49; negative 25/49; excited component: 9/35; general 40/112. Hamilton-anxiety: 24/56; clozapine: 594 ng/mL; norclozapine: 470 ng/mL, respectively. Aripiprazole 10 mg/d was added to clozapine (dose unchanged) and lorazepam (1 mg/d) was discontinued. The patient was discharged three weeks after the aripiprazole addition.\nA followup over 3 months did not reveal any change in the CGI and PANSS scores (at 3 months: CGI : 4; total PANSS: 73; positive: 20/49; negative: 25/49; excited component: 7/35; general: 40/112), while the Hamilton-anxiety score diminished progressively to 19 and 15 after one and three months, respectively. The clozapine and norclozapine plasma concentrations at three months were 431 ng/mL and 343 ng/mL, respectively.