Key takeaways
Azithromycin (Zithromax) and Clarithromycin (previously known as Biaxin) are both macrolide antibiotics used to treat various bacterial infections. Azithromycin is typically taken once daily for 3 to 5 days, while Clarithromycin is usually taken twice daily for 7 to 14 days, though it also has an extended-release form taken once daily. Azithromycin is available as a lower-cost generic and comes in tablet and liquid forms, making it convenient for those who have trouble swallowing pills. Clarithromycin also comes in generic form and is available as immediate-release tablets, extended-release tablets, and a liquid. Azithromycin is used for infections like strep throat, pneumonia, and certain sexually transmitted infections, whereas Clarithromycin is also used for treating stomach ulcers caused by *Helicobacter pylori* and infections in people with HIV. Both medications can cause side effects like diarrhea and stomach pain, but Clarithromycin is more likely to cause a metallic or sour taste. Additionally, Clarithromycin has more drug interactions and is not recommended during pregnancy, while Azithromycin is generally considered safer for pregnant individuals.
