Elevation of plasma concentrations of haloperidol after the addition of fluoxetine

Abstract
Fluoxetine (20 mg/day) was added for 7-10 days to stable doses of haloperidol given to eight psychotic patients. Mean plasma concentrations of haloperidol were elevated by 20% (p less than 0.05), but extrapyramidal side effects did not increase appreciably, indicating a relatively minor interaction between these agents.