MedlinePlus states that azithromycin treats certain bacterial infections, including bronchitis, pneumonia, sexually transmitted diseases, and infections of the ears, lungs, sinuses, skin, throat and reproductive organs. It is also used to prevent and treat disseminated Mycobacterium avium complex, which is a lung infection that often affects those with HIV. Occasionally, azithromycin is used to treat gastrointestinal infections, Legionnaires' disease, pertussis, and babesiosis.
MedlinePlus explains that azithromycin is sometimes used to prevent sexually transmitted diseases in patients who have been sexually assaulted and to prevent heart infection in people having certain procedures. Before taking azithromycin, a patient needs to provide his doctor with a list of his medication allergies and all current medications, vitamins and supplements he is taking. This allows the doctor to check for any interactions. The patient is advised to inform his doctor if he has a personal or family history of a heart condition called prolonged QT interval or a history of fast, slow or irregular heartbeat. Before a doctor prescribes azithromycin, he also needs to know if the patient has a history of low blood levels of magnesium or potassium or if the patient has a blood infection, heart failure, cystic fibrosis, AIDS or HIV, myasthenia gravis, kidney disease or liver disease.