title: Comparative in vitro activity of the new oral macrolide azithromycin.
abstract: The in vitro activity of the new oral macrolide azithromycin was compared with that of erythromycin against gram-positive and gram-negative aerobic and anaerobic bacteria. Ninety percent of hemolytic streptococci groups A and B, and Streptococcus pneumoniae were inhibited by 0.5 microgram/ml. Activity of azithromycin was similar to that of erythromycin; erythromycin-resistant staphylococci and streptococci were not inhibited. Azithromycin was more active than erythromycin against Haemophilus influenzae (MIC90 1 microgram/ml) and Neisseria gonorrhoeae. It inhibited Campylobacter spp. and Pasteurella multocida, and had an MIC50 of 8 micrograms/ml for Escherichia coli, Salmonella spp., Shigella spp. and Yersinia enterocolitica compared to an erythromycin value of greater than 64 micrograms/ml.
authors.affiliation: Department of Medicine, College of Physicians & Surgeons, Columbia University, New York, New York 10032.
authors.forename: H C
authors.initials: HC
authors.lastname: Neu
authors.forename: N X
authors.initials: NX
authors.lastname: Chin
authors.forename: G
authors.initials: G
authors.lastname: Saha
authors.forename: P
authors.initials: P
authors.lastname: Labthavikul
mesh_terms: D017963:Azithromycin; D001419:Bacteria / Q000187:drug effects*; D004917:Erythromycin / Q000031:analogs & derivatives* / Q000494:pharmacology; D006190:Haemophilus / Q000187:drug effects; D013210:Staphylococcus / Q000187:drug effects; D013291:Streptococcus / Q000187:drug effects
chemical_list: D004917:Erythromycin; D017963:Azithromycin