Compare Clarithromycin vs. Azithromycin

Clarithromycin (previously known by its brand name Biaxin) and azithromycin (Zithromax) are both macrolide antibiotics used to treat various bacterial infections, such as pneumonia, sinus infections, and strep throat. However, they differ in several ways. Clarithromycin is available as an immediate-release tablet, extended-release tablet, and liquid, while azithromycin is available as tablets and liquid, often in a convenient Z-Pak. Clarithromycin is typically taken twice a day, whereas azithromycin is taken once daily, with treatment usually lasting 3 to 5 days. Clarithromycin can treat *Helicobacter pylori* infections, which azithromycin cannot, while azithromycin can treat certain sexually transmitted infections, which clarithromycin cannot. Both medications can cause side effects like diarrhea and stomach pain, but clarithromycin may also cause a metallic taste. Clarithromycin has more drug interactions, especially with statins like lovastatin and simvastatin, while azithromycin can interact with antiarrhythmics and statins, raising the risk of heart rhythm problems. Both medications are available as lower-cost generics.