Grepafloxacin is primarily used as an antibiotic to treat various bacterial infections. It is effective against respiratory tract infections, including bronchitis and pneumonia, by inhibiting bacterial DNA gyrase and topoisomerase IV, which are essential for bacterial DNA replication. It is also used for treating urinary tract infections and certain sexually transmitted infections caused by susceptible bacteria. Due to its broad-spectrum activity, it is particularly useful in cases where other antibiotics may be less effective. However, its use has been limited in some regions due to concerns about potential side effects, such as cardiac issues.