are there pharmacokinetic interactions involving citalopram and fluoxetine?
OBJECTIVE: Therapeutic drug monitoring (TDM) of the new generation antidepressants is subject of controversial discussion. Nonetheless, TDM may safeguard against drug-drug interactions, can be used to control compliance and is valuable in the investigation of overdose. METHOD: The aim of this prospective study was to investigate serum levels of trazodone when prescribed as monotherapy or when used in combination with the selective serotonin reuptake inhibitors citalopram and fluoxetine in a simultaneous assay using high-performance liquid chromatography (HPLC). Over a 1-year period, we studied 97 patients (63 females) with depressive syndrome who were subdivided into 3 main diagnostic groups. Fifty-two patients were smokers, the mean age was 39.9 years and the mean weight was 72.4 kg; 40 patients were taking trazodone alone, 41 trazodone in combination with citalopram and 16 patients trazodone in combination with fluoxetine. RESULTS: The use of citalopram and fluoxetine in combination