Effect of antipyretic agents on uptake, transport, and release of antimicrobial agents by human polymorphonuclear leukocytes.

Polymorphonuclear leukocytes (PMNL) concentrate, transport, and release certain antimicrobial agents as they move in a chemotactic gradient. Antipyretic agents are frequently used in febrile patients receiving antimicrobial agents. Thus, the influence of ibuprofen, acetaminophen, and acetylsalicylic acid on uptake, transport, and release of azithromycin and moxifloxacin was studied. Uptake of the antimicrobial agents by human PMNL and the effect of the antipyretics were quantitated by bioassay of released antimicrobial agent. Transport and release were determined in chemotactic plates overlaid with sentinel bacteria that could detect transported and released antimicrobial agent. None of the antipyretics altered PMNL directed or non-directed movement. Uptake of azithromycin was significantly inhibited by acetylsalicylic acid but not by the other antipyretics. All of the antipyretic agents studied at therapeutic levels inhibited transport and release of both azithromycin and moxifloxacin. Administration of any of these antipyretic agents with antimicrobial agents that are transported and released by PMNL could compromise the efficacy of therapy.