Tiospirone in chronic treatment-resistant schizophrenics

Tiospirone may be a novel antipsychotic. In animals it blocks dopamine, σ-opiate, and serotonergic receptors, but has a low tendency to produce catalepsy and does not induce dopamine receptor supersensitivity in vitro (Eison et al. 1984; McMillen 1985). A single-blind 4 week clinical study in 14 male schizophrenics with dosage up to 180 mg/day showed significant improvement in psychopathology without the appearance of extrapyramidal symptoms (Moore et al. 1987). Similar results were reported in a single-blind crossover study comparing tiospirone with standard neuroleptics in schizophrenic patients (Jain et al. 1987). The present study was conducted as part of a single-blind multicentre investigation to assess the efficacy and tolerability of tiospirone in hospitalised treatment-refractory schizophrenic patients. A flexible dose schedule of 150 to 500 mg/day for 12 weeks was used. Unfortunately, the clinical trial was suspended by the sponsor for administrative reasons (reassessment of priorities) before our participation could be completed. In addition to the study protocol, we were also interested in changes in the α-EEG spectral energy. The α-energy band is increased following administration of standard and atypical neuroleptics such as clozapine (Small et al. 1987). We found that changes in the α-energy reflect abnormalities in schizophrenia (Jin et al. 1988), and that these changes normalise with neuroleptic treatment (Potkin et al. 1989).