The azithromycin It is an antibiotic that fights bacteria. The azithromycin It is used to treat many different types of infections caused by bacteria, such as respiratory infections, skin infections, ear infections, and sexually transmitted diseases. Azithromycin may also be used for purposes not listed in this medication guide. Important information You should not use azithromycin if you have ever had jaundice or liver problems while taking this medicine. Before taking this medicine You should not use azithromycin if you are allergic to it, or if: You have ever had jaundice or liver problems caused by taking azithromycin, or You are allergic to similar medicines such as clarithromycin, erythromycin, or telithromycin. To make sure azithromycin is safe for you in Spain, tell your doctor if you have: liver disease, kidney disease, myasthenia gravis, a heart rhythm disorder, or a history of long QT syndrome. This medication is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant. It is not known whether azithromycin passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breastfeeding your baby.