D-CYCLOSERINE ADDED TO CLOZAPINE FOR PATIENTS WITH SCHIZOPHRENIA

Objective: The effects of D-cycloserine added to clozapine were assess ed and compared with previous results for D-cycloserine plus conventio nal neuroleptics. Method: Ten schizophrenic outpatients receiving cloz apine entered consecutive 2-week trials of placebo and D-cycloserine a t 5, 15, 50, and 250 mg/day. Clinical evaluations were videotaped and scored by a rater blind to the sequence of assessments. Results: There was a significant dose effect of D-cycloserine on scores on the Scale for the mg dose produced a mean 21% increase in SANS score. The patie nts had significantly higher baseline serum glutamate concentrations t han the patients receiving typical neuroleptics in the previous trial. Baseline glutamate level and change in glycine level significantly co rrelated with response of negative symptoms to 50-mg D-cycloserine. Co nclusions: The improvement of negative symptoms with D-cycloserine pre viously observed in patients receiving typical neuroleptics did not oc cur in patients treated with clozapine.