The human pharmacology of fluoxetine

Fluoxetine is a potent and specific inhibitor of 5-HT uptake even after prolonged dosing. Both fluoxetine and norfluoxetine, an active metabolite, have a long plasma half life. The drug is extensively metabolized and undergoes renal elimination. Impairment of renal function, increasing age or obesity do not appear to alter the disposition of fluoxetine, although hepatic impairment predictably decreases the clearance of the drug. Recent data suggests that fluoxetine is an inhibitor of cytochrome P450-II-D6 in man and has been shown to inhibit the metabolism of a number of drugs which are substrates for this isoenzyme. It does not, however, affect the elimination of ethanol and does not enhance the effect of ethanol on psychometric testing. Fluoxetine has no effect on normal blood pressure although mean heart rate is slightly reduced. It does not appear to have a clinically significant effect on pituitary function. Although there is psychometric and EEG evidence to suggest a vigilance enhancing property, fluoxetine does not exhibit stimulant activity of the amphetamine type and has been shown to be well tolerated at doses clinically useful for appetite suppression in extensive clinical trials and widespread clinical use since marketed in 1987 for depressive illness.