Drug Interaction Report

GENERALLY AVOID: Coadministration of topical chloramphenicol with other agents that can cause bone marrow depression, aplastic anemia, or agranulocytosis may increase the risk and/or severity of hematologic toxicity. Chloramphenicol may be absorbed systemically from the eye, ear, and vagina. Bone marrow hypoplasia, including aplastic anemia and death, has been reported following topical use of chloramphenicol. However, systemic absorption following topical, ophthalmic, otic, and vaginal administration is generally minimal, and data concerning the incidence of blood dyscrasias following the use of topical chloramphenicol are not available.

MANAGEMENT: Concurrent use of topical chloramphenicol formulations with other bone marrow depressing agents should generally be avoided. If concomitant use on a long-term or intermittent basis is considered necessary, patients should be monitored for the development of hematologic adverse effects. Monitoring via full blood counts before and periodically during therapy may also be advisable.

ADJUST DOSING INTERVAL: Food enhances the oral bioavailability of bosutinib. When given with a high-fat meal, bosutinib peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 1.8- and 1.7-fold, respectively.

GENERALLY AVOID: Coadministration with grapefruit juice is likely to increase the plasma concentrations of bosutinib, which is primarily metabolized by CYP450 3A4. However, the interaction has not been studied. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit.

MANAGEMENT: Bosutinib should be administered with a meal. The consumption of grapefruit, grapefruit juice, and supplements that contain grapefruit extract should be avoided.