Moxifloxacin is an antibiotic. Moxifloxacin ophthalmic solution is used to treat bacterial conjunctivitis, endocarditis, tuberculosis, and sinusitis. Moxifloxacin is in a class of antibiotics called fluoroquinolones. It works by killing the bacteria that cause infection. It can be given by mouth, by injection into a vein, and as an eye drop.