Levofloxacin can usually be taken continuously for about 2 weeks and is not recommended to be taken for 28 consecutive days. If patients take levofloxacin for 28 consecutive days, they may develop drug resistance or aggravate adverse reactions, such as gastrointestinal discomfort and kidney function impairment. Usually patients take levofloxacin for about 2 weeks continuously, if the symptoms do not improve, it is recommended to choose to change to other types of antibiotics for treatment. Levofloxacin belongs to the quinolone antibiotics, which can treat infectious diseases caused by Gram-negative and Gram-positive bacteria, such as inflammation of the urinary system, inflammation of the respiratory system, inflammation of the digestive system, and inflammation of the skin and soft tissues. Levofloxacin is not recommended clinically for patients under 18 years of age, patients with myasthenia gravis, patients during pregnancy and lactation, and patients with hypersensitivity to quinolones. Patients who have been taking levofloxacin for about 2 weeks and still cannot relieve their symptoms indicate that the antibacterial effect of the drug is not good. It is necessary to adjust the antibiotic treatment regimen and choose cefixime, erythromycin, roxithromycin, streptomycin, gentamicin, tetracycline, chloramphenicol and other drugs to improve the poor therapeutic effect of levofloxacin. If levofloxacin is taken for 28 days continuously, it is easy to induce bacterial resistance, which makes clinical treatment more difficult, worsens the condition and even threatens life. Some patients taking levofloxacin for a longer period of time may also lead to serious adverse consequences, such as diarrhea, nausea, headache, dizziness, itchy skin, etc. In severe cases, irritability, hallucinations, joint pain, drowsiness, shock, seizures, and mental abnormalities may occur. If the patient suffers from diabetes, hypertension, heart disease, liver and kidney disease, stomach disease, psychosis, epilepsy, or is taking Class II or Class III antiarrhythmic drugs, care should be taken to take levofloxacin in appropriate amounts, otherwise the QT interval of the heart may be prolonged and arrhythmias may occur, etc. Patients taking levofloxacin should avoid taking acid-suppressing, metal ion-containing drugs and ibuprofen, iproniazid, cyclosporine, etc. at the same time.