Zithromax is a prescription antibiotic medication, and a patient can only legally purchase this medication from a pharmacy, explains Drugs.com. Patients take Zithromax to treat a variety of bacterial infections, including respiratory, skin and ear. Zithromax also treats some sexually transmitted diseases.
Azithromycin is the generic name for Zithromax, and it is similar to clarithromycin, erythromycin and telithromycin. Patients who have had allergic reactions to similar drugs may have allergic reactions to Zithromax and should inform their doctors. Patients with liver disease, kidney disease, myasthenia gravis, Long QT syndrome or heart rhythm disorders should not take Zithromax unless closely monitored by their doctors, according to Drugs.com.