A course of Levofloxacin Injection is about seven days, but it varies according to the disease. 1. Urinary tract infection, you can use levofloxacin injection and other drugs for treatment, a course of treatment is three to seven days, its concentration in the urine is relatively high, so the effect against the common germs of the urinary system infection is relatively good. 2. usually treat diarrhea, if there is no fever, do not need to take antibacterial drugs, if the fever, a course of treatment is to apply 3 to 7 days levofloxacin injection can be. If the diarrhea is more serious, or accompanied by symptoms of fever, you need to carry out infusion treatment, but also can be combined with the application of vitamin C, potassium chloride and metoclopramide to carry out treatment.