The results clearly demonstrate the superiority of antipsychotic drugs compared to placebo in preventing relapse. This effect must be weighed against the side effects of antipsychotic drugs. Future studies should focus on outcomes of social participation and clarify the long-term morbidity and mortality associated with these drugs.
Persistence of fluphenazine in plasma after decanoate withdrawal.
We discontinued fluphenazine decanoate using a double-blind, crossover random order design, in 12 recent onset clinically stable schizophrenics who had been given fluphenazine decanoate 12.5 mg intramuscularly every 2 weeks for at least 1 year prior to drug withdrawal. Each condition (drug or placebo) lasted 12 weeks. Using a radioimmunoassay verified by comparison to a gas chromatographic-mass spectrometric method, plasma fluphenazine levels were measured every 2 weeks during drug continuation and drug withdrawal conditions. No patient relapsed over the 24-week period of the study. Mean fluphenazine levels between drug continuation and withdrawal conditions showed a progressively larger difference over time, although significant differences were not seen until week 8. By week 12 after drug withdrawal, 33% of subjects still showed notable plasma fluphenazine levels. On the basis of our preliminary findings, we suggest that 2-week intervals between injections may be too short and that wider intervals may achieve similar clinical results.