The regular of doses given. The digestive system. This medicine is a macrolide antibiotic used to treat bacterial infections. Taking this medicine at the same time each day will make it easier to remember. Common side effects of Azithromycin are normally well tolerated. This drug is that it is found to be present in the body for a significant period of time after the required doses. The majority of infections, Zithromax is prescribed once daily for a relatively short course of treatment, where the first dose is frequently a double dose, two times as much as the regular of doses given.