Abstract: AIM: To observe the clinical safety of azithromycin with low-dose and long-term usage. METHODS: The safety profile was assessed in 76 patients with chronic respiratory tract infective diseases received 0.25 g azithromycin once a day over 6 weeks orally;and 62 patients by 0.5 g amoxicillin three times a day over 6 weeks orally. RESULTS: The rate of side effects was 10.5% with azithromycin, similar to that with amoxicillin (P > 0.05);but rate of skin rash was increased in the patients with amoxicillin (P <0.05). CONCLUSION: The long-term usage of azithromycin with low-dose was safety in treatment of patients with chronic respiratory tract infective diseases.

Key words: pharmacodynamics, azithromycin, sideeffects, chronic respiratory tract infection