Pizotifen increases 5-HIAA urinary excretion in male healthy volunteers.
A single dose of 0.5 mg pizotifen or a placebo was administered to 10 healthy male volunteers in a double blind cross-over trial. 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) in hourly urine samples were determined by liquid chromatography with amperometric detection. The 5-HIAA levels were strongly correlated with the HVA levels in control samples (r = 0.95, p less than 0.001). Pizotifen produced a significant increase in the urinary 5-HIAA/HVA ratio over the 3 hours following absorption of the drug (+0.21, +0.18, +0.19, p less than 0.05). The increase demonstrates an interaction between pizotifen and 5-HT metabolism, which may be involved in its antimigraine effect.
D000328:Adult; D004298:Dopamine / Q000378:metabolism; D004311:Double-Blind Method; D006719:Homovanillic Acid / Q000378:metabolism; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000652:urine*; D008297:Male; D010918:Pizotyline / Q000494:pharmacology*; D011897:Random Allocation; D012701:Serotonin / Q000378:metabolism; D013876:Thiophenes / Q000494:pharmacology*
D013876:Thiophenes; D010918:Pizotyline; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D004298:Dopamine; D006719:Homovanillic Acid