Chest infections and pneumonia, sinusitis, throat and ear infections, some skin infections, typhoid fever, and sexually transmitted infections such as chlamydia. It is often chosen for people who cannot take penicillin.

Azithromycin binds to the bacterial ribosome, the machine a bacterium uses to turn its genes into proteins. With the ribosome jammed the bacterium cannot make the proteins it needs to grow and divide, so the infection stops spreading while the immune system clears it.

Nausea, stomach pain, diarrhoea, vomiting and headache. Taste changes and temporary hearing changes are less common.

Azithromycin can affect the heart's electrical rhythm, so tell your doctor about a slow or irregular heartbeat, a long QT interval, low potassium or magnesium, or other medicines that affect rhythm. Report severe or bloody diarrhoea, or yellowing of the skin or eyes. Finish the course as prescribed. It is a prescription medicine in Pakistan.