Azithromycin is used for respiratory and mycobacterium avium infections. Mycobacterium avium is the organism that tends to affect HIV patients. We can’t cure this infection because it’s extremely slow growing. In order to kill the organism, the organism needs to be growing. This antibiotic is commonly utilized when a person has a respiratory infection.
Clarithromycin is also used for the same things as azithyromycin with the addition of helicobacter pylori. Helicobacter pylori is associated with ulcers.  Most ulcers are not a GI disease, but an infectious disease.  But that doesn’t mean that everyone with an ulcer will have this organism.  It’s just that if that organism is present, we treat it as an infectious disease. Before, people were on chronic anti-ulcer therapy for their entire lives until they discovered this organism. A 14-day course of this antibiotics not only makes them less prone to ulcers but it’s a cure.
- Azithromycin (Zithromax®) – Respiratory infection, mycobacterium avium
- Clarithromycin (Biaxin®) – Respiratory infection, mycobacterium avium, helicobacter pylori
