The prediction of clozapine discontinuation

clozapine is also accompanied by increases in the CSF HVA:5HIAA ratio. Eight medication flee patients meeting RDC criteria for schizophrenia received research lumbar punctures prior to the initiation of clozapine therapy and after approximately 42 weeks of clozapine therapy. There was no group mean significant change in the CSF HVA:SHIAA ratio accompanying clozapine phannacotherapy. However, in the group as a whole **CSF HVA:SHIAA ratio was significantly correlated with **BPRS and **BPRS subscales, in the three of the eight subjects who experienced significant clinical improvement on clozapine phannacotherapy, there was a substantial increase in the CSF HVA:SHIAA ratio. In the remaining five patients, who showed little improvement or significant worsening with clozapine phannacotherapy, there was only a very small increase no change or a significant decrease in the HVA: 5HIAA ratio. These preliminary results of CSF catecholamine changes with the "atypical" neuroleptic clozapine are remarkably consistent With the pattern of response associated with antipsychotic response to the "typical" neuroleptic haloperidol reported by Kahn et al. These data add further credence to the proposals by Meltzer and others that CNS dopaminergicserotonergic interactions may be mechanistically important in understanding antipsychotic pharmacotherspy.