title: The use of stable isotopes to prove the saturable first-pass effect of methoxsalen.
abstract: Methoxsalen, administered orally shows a strong, albeit saturable first-pass effect, as demonstrated by classical dose linearity testing and by a new method, using stable isotopes and gas chromatographic mass spectrometric analysis. The therapeutic consequences of the first-pass effect are discussed.
mesh_terms: D000328:Adult; D001682:Biological Availability; D003903:Deuterium; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D008297:Male; D008730:Methoxsalen / Q000378:metabolism* / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D003903:Deuterium; D008730:Methoxsalen