Azithromycin is an antibiotic that fights bacteria. Azithromycin is used to treat many different types of infections caused by bacteria, such as respiratory infections, skin infections, ear infections, eye infections, and sexually transmitted diseases. Learn about the side effects of azithromycin, from common to rare, for consumers and healthcare professionals. Azithromycin is in a class of medications called macrolide antibiotics. It works by stopping the growth of bacteria. Antibiotics such as azithromycin will not work for colds, flu, or other viral infections. Using antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment. Azithromycin, sold under the brand names Zithromax (in oral form) and Azasite (as an eye drop), is an antibiotic medication used to treat several bacterial infections. [9] Azithromycin (Zithromax) is a macrolide antibiotic. It's used to treat many types of infections in children and adults, including strep throat, sinus infection, and pneumonia. Indicated for treatment of community-acquired pneumonia due to Chlamydophila pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, or Streptococcus pneumoniae in patients appropriate for oral. Azithromycin belongs to the class of drugs known as macrolide antibiotics. It works by killing bacteria or preventing their growth. However, this medicine will not work for colds, flu, or other virus infections. This medicine is available only with your doctor's prescription. Azithromycin (Zithromax) is an antibiotic medication that treats bacterial infections. It doesn’t treat viral infections. Azithromycin is used to treat certain bacterial infections (including sinusitis, pneumonia, ARDS, and acute bronchitis). It is a macrolide-type antibiotic. It works by stopping the growth of bacteria. This medication will not work for viral infections (such as common cold, or flu). Overview: Azithromycin is an antibiotic that is used to treat certain bacterial infections. It works by stopping certain types of bacteria from making proteins they need to grow and multiply..