Macrolides

Macrolides stop bacteria from making proteins by binding to their ribosomes. Azithromycin treats respiratory infections, including atypical pneumonia, as well as chlamydia and some skin infections, and it is often used when someone is allergic to penicillin. Nausea, diarrhea, and stomach cramping are common. Macrolides can prolong the QT interval, and erythromycin and clarithromycin interact with many other drugs.

• AzithromycinKnown brand names include Zithromax.