a macrolide antibiotic that is isolated from the culture fluid of the actinomycete Streptomyces antibioticus. Oleandomycin suppresses the growth of gram-positive bacteria, primarily staphylococci, streptococci, and pneumococci. When oleandomycin is combined with tetracycline, the antimicrobial action is potentiated. Oleandomycin is used in infectious diseases of the lungs and of the urinary and biliary tracts; it is also used in other diseases that are caused by microbes that are resistant to antibiotics and sensitive to oleandomycin. Oleandomycin is effective against the same spectrum of bacteria as erythromycin.