Medscape - Infection-specific dosing for Zithromax, Zmax (azithromycin), frequency-based 250 mg PO once daily in combination with ethambutol 15 mg/kg/day with or without Chlamydia trachomatis, Haemophilus ducreyi, Haemophilus influenzae, Legionella spp, . Use caution in renal impairment (CrCl 10...