The main difference between Roxithromycin and Azithromycin is the different antibacterial spectrum and adverse reactions, patients should choose the medication according to their own situation, under the guidance of the doctor. 1. Antibacterial spectrum: Roxithromycin is the first generation of fourteen macrolide antibiotics, azithromycin is the second generation of fifteen macrolide antibiotics. Usually, azithromycin is more effective for infections caused by mycoplasma or chlamydia bacteria, and erythromycin is more effective for infections caused by sensitive bacteria. 2. Adverse reactions: the common adverse reactions of erythromycin are abdominal pain, diarrhea, nausea, vomiting and other gastrointestinal reactions, and occasional rash, itchy skin, dizziness, headache, liver function abnormalities, peripheral blood cell decline and other symptoms. The common adverse reactions of azithromycin are gastrointestinal reactions, such as diarrhea, loose stools, nausea, abdominal pain, vomiting, etc.; rare dyspepsia, abdominal distension, mucositis, oral candidiasis, gastritis, headache, drowsiness, bronchospasm, taste inversion and other adverse reactions. If you need to take roxithromycin and azithromycin, it is recommended to consult a professional doctor and follow the doctor’s instructions for standardized treatment, not blindly self-medication.