The effect of antipsychotic medication on relative cerebral blood perfusion in schizophrenia: assessment with technetium-99m hexamethyl-propyleneamine oxime single photon emission computed tomography

Biol Psychiatry. 1997 Mar 1;41(5):550-9. doi: 10.1016/s0006-3223(96)00110-2.


Functional neuroimaging studies in schizophrenia have often been confounded by various factors including medication status. To explore the effects of antipsychotic medications on relative regional cerebral perfusion, we scanned a group of 33 persons with schizophrenia twice, while receiving a stable dose of antipsychotic and after being off antipsychotics for 3 weeks, using technetium-99m hexamethyl-propyleneamine oxime single photon emission computed tomography (Tc-99m HMPAO-SPECT. We found that antipsychotic significantly increased the mean relative cerebral perfusion in the left basal ganglia. Additionally, patients receiving thiothixene (n = 9) had a significantly greater increase in relative cerebral perfusion in the basal ganglia than patients receiving haloperidol (n = 12). These findings indicate that antipsychotics lead to regional increases in cerebral perfusion and that antipsychotic status must be controlled for in functional neuroimaging studies. Functional neuroimaging techniques such as SPECT may be useful in furthering our understanding of the mechanism of antipsychotics.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Antipsychotic Agents / adverse effects
  • Antipsychotic Agents / therapeutic use*
  • Basal Ganglia / blood supply
  • Brain / blood supply*
  • Brain Mapping
  • Cerebellum / blood supply
  • Cerebral Cortex / blood supply
  • Chronic Disease
  • Clozapine / adverse effects
  • Clozapine / therapeutic use
  • Female
  • Haloperidol / adverse effects
  • Haloperidol / therapeutic use
  • Humans
  • Male
  • Organotechnetium Compounds
  • Oximes
  • Psychiatric Status Rating Scales
  • Regional Blood Flow / drug effects
  • Regional Blood Flow / physiology
  • Schizophrenia / diagnostic imaging
  • Schizophrenia / drug therapy*
  • Schizophrenia / physiopathology
  • Schizophrenic Psychology*
  • Technetium Tc 99m Exametazime
  • Thiothixene / adverse effects
  • Thiothixene / therapeutic use
  • Tomography, Emission-Computed, Single-Photon*
  • Trifluoperazine / adverse effects
  • Trifluoperazine / therapeutic use


  • Antipsychotic Agents
  • Organotechnetium Compounds
  • Oximes
  • Trifluoperazine
  • Technetium Tc 99m Exametazime
  • Thiothixene
  • Clozapine
  • Haloperidol