title: Different actions of neomychin and metronidazole on breath hydrogen (H2) exhalation.
abstract: Purpose of this investigation was to characterize the effect of antibiotics as a possible limiting factor for the evaluation of hydrogen (H2) breath analysis tests which depend on bacterial carbohydrate fermentation. Breath H2-excretion following ingestion of the non-absorbable disaccharide lactulose was monitored in healthy subjects before and after pretreatment with the aminoglycoside neomycin or with metronidazole. Metronidazole decreased the amount of hydrogen exhaled by 39 % (p<0.05) and peak H2-excretion by 42.1 % (p<0.01), because it suppresses anaerobe H2 producing microorganisms. Neomycin intensified nonsignificantly the integrated (0-6 hours) breath hydrogen response to lactulose (+43 %) and the maximal H2-concentration by 29.8 %, probably because it interferes with intestinal bacteria which are important for H2-consumption.
mesh_terms: D000328:Adult; D001944:Breath Tests; D005260:Female; D006801:Humans; D006859:Hydrogen / Q000378:metabolism*; D007422:Intestines / Q000382:microbiology; D007792:Lactulose; D008297:Male; D008795:Metronidazole / Q000494:pharmacology*; D009355:Neomycin / Q000494:pharmacology*
chemical_list: D008795:Metronidazole; D007792:Lactulose; D006859:Hydrogen; D009355:Neomycin