The present invention relates to an aqueous pharmaceutical composition comprising a) 0.01 to 30 percent by weight of a quinolone compound being selected from the group consisting of orbifloxacin grepafloxacin nalidixic acid sparfloxacin or trovafloxacin mesylate b) 0.2 to 20 percent by weight of an ion exchange resin prepared from a porous copolymer of methacrylic acid crosslinked with divinylbenzene and c) pharmaceutically acceptable excipients to equal 100 percent.