passages.id: split_1_test_2033_passage
passages.type: progene_text
passages.text: The metabolite , 3-phenoxybenzoic acid ( 3-PBA ) , can be derived from several pyrethroids and is , therefore , a useful diagnostic analyte ; however , the presence of the over-the-counter drug , ibuprofen ((R,S)-2-(4-isobutylphenyl ) propionic acid ) , interferes with this determination , even after the ingestion of only one 200 - mg tablet .