Effect of fluoxetine, pemoline and placebo on heart period and QT variability in normal humans.
OBJECTIVE
To measure the effects of fluoxetine and pemoline on heart period and QT variability.


METHODS
Healthy volunteers were randomly assigned treatment with 20 mg daily of fluoxetine (n=7), 56.25 mg of pemoline (n=7) or placebo (n=9). Twenty-four-hour Holter ECGs were obtained before and after approximately 8 weeks of double-blind treatment.


RESULTS
There were no significant changes in the fluoxetine group. Pemoline was associated with a significant decrease in the high frequency (HF) power (0.15-0.5 Hz, P=.02) and fractal dimension of RR time series (P=.03). QTvi, a measure of QT interval variability, increased in the pemoline group (P=.05).


CONCLUSIONS
Pemoline, but not fluoxetine, decreases heart period variability (HPV) in the HF power, suggesting a vagolytic effect on cardiac autonomic function. Pemoline is also associated with an increase in QT interval variability, a measure that is sensitive to adrenergic agonists.
Pohl
Robert
R
Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, 2751 E. Jefferson, Detroit, MI 48207, USA.
Balon
Richard
R
Jayaraman
Anusha
A
Doll
Ronald G
RG
Yeragani
Vikram
V
D000328:Adult; D001008:Anxiety Disorders / Q000150:complications / Q000188:drug therapy; D002302:Cardiac Output / Q000187:drug effects*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D016757:Death, Sudden, Cardiac; D003866:Depressive Disorder / Q000150:complications / Q000188:drug therapy; D004569:Electroencephalography; D005260:Female; D005473:Fluoxetine / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D010389:Pemoline / Q000494:pharmacology*; D010919:Placebos; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology*
D000697:Central Nervous System Stimulants; D005473:Fluoxetine; D010389:Pemoline; D010919:Placebos; D017367:Selective Serotonin Reuptake Inhibitors