The most frequently reported drug-related adverse events in clinical studies were diarrhea (3.6%), rash (2.8%), and nausea (2.7%). The discontinuation rate due to related adverse events in clinical studies was low (2.2%).

In clinical trials, drug-related rash was reported in 2.8% of patients receiving gemifloxacin and was more commonly observed in patients <40 years of age, especially females. The incidence of rash increases with treatment longer than the maximum-labeled duration of 7 days.

Gemifloxacin is contraindicated in patients with a history of hypersensitivity to gemifloxacin, fluoroquinolone antibiotic agents, or any of the product components.

Patients receiving marketed fluoroquinolones have reported serious and occasionally fatal hypersensitivity and/or anaphylactic reactions, peripheral neuropathy, antibiotic associated colitis, and tendon ruptures. Gemifloxacin should be discontinued immediately at the first sign of any of these events.

Fluoroquinolones may prolong the QT interval in some patients. Gemifloxacin should be avoided in patients with a history of prolongation of the QTc interval, patients with uncorrected electrolyte disorders (hypokalemia or hypomagnesemia), and patients receiving Class IA or Class III antiarrhythmic agents.

In clinical studies with gemifloxacin, CNS effects have been reported infrequently. As with other fluoroquinolones, gemifloxacin should be used with caution in patients with known or suspected CNS diseases. If CNS reactions occur, gemifloxacin should be discontinued and appropriate measures instituted.

The safety and effectiveness of gemifloxacin in children, adolescents (<18 years of age), pregnant women, and lactating women have not been established.