To evaluate the clinical efficacy and safety in patients with Acute Bronchitis or Secondary Infection of Chronic Respiratory Diseases receiving a dose of 2 g of azithromycin in the SR formulation.

Inclusion Criteria:

• Patients who were diagnosed as mild or moderate in severity by the classification of infection of the Japanese Society of Chemotherapy guidelines for the evaluation methods of new antibacterial drug (established in 1997).

Exclusion Criteria:

• Severe underlying disease; patients in which drug clinical evaluation is difficult because of confounding diseases.