title: Investigation of the Urinary excretion of pethidine and five of its metabolites in man using selected ion monitoring.
abstract: The urinary excretion in man of pethidine and five of its metabolites (norpethidine, pethidinic acid, norpethidinic acid, p-hydroxypethidine and pethidine N-oxide) after a single intramuscular dose has been investigated using analytical procedures based on selected ion monitoring. New methods for the determination of p-hydroxypethidine and pethidine N-oxide have been developed, and the selectivity and sensitivity of the procedures are discussed. Only some 5% of the administered dose was excreted as unchanged pethidine. The mean urinary excretion of norpethidine was 16.4%. Pethidinic acid and norpethidinic acid constituted the major fraction of the dose excreted in urine. The total excretion of pethidinic acid and norpethidinic acid was 41.7 and 23.2%, respectively. Pethidine N-oxide constituted less than 0.5% of the excreted amount, and p-hydroxypethidine could only be detected in the urine of two of the patients. A mean total recovery of about 90% of the dose was found in urine as pethidine and the five metabolites.
mesh_terms: D000328:Adult; D003903:Deuterium; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007273:Injections, Intramuscular; D007747:Labor Stage, First; D008614:Meperidine / Q000378:metabolism / Q000652:urine*; D011247:Pregnancy; D013997:Time Factors
chemical_list: D008614:Meperidine; D003903:Deuterium