Azithromycin is an antibiotic. It works by preventing synthesis of essential proteins required by bacteria to carry out vital functions. Thus, it stops the bacteria from growing, and prevents the infection from spreading. Lactic acid bacillus is a beneficial lactic acid-producing bacteria that supports the growth of friendly bacteria in the intestine and maintains a healthy balance of microflora in the gut environment. It is used to restore good bacteria and reduce stomach upset and diarrhoea.