The present invention provides compositions and methods for administering florfenicol to mammals. The compositions contain a prodrug of florfenicol in a pharmaceutically acceptable carrier. In one embodiment the prodrug is an esterized form of florfenicol. Examples of suitable prodrugs include one or a combination of one or a combination of the following: florfenicol acetate, florfenicol propionate, florfenicol butyrate, florfenicol pentanoate, florfenicol hexanoate, florfenicol heptanoate, florfenicol octanoate, florfenicol nanoate, florfenicol decanoate, florfenicol undecanoate, florfenicol dodecanoate, and florfenicol phthalate. In another embodiment the prodrug is converted into the florfenicol in vivo by the action of one or more endogenous esterases. The invention also provides new compounds, pharmaceutical compositions containing the compounds, and methods for their administration.