Antibiotics are a type of antimicrobial drug that is used to treat bacterial infections. They work by killing or inhibiting the growth of bacteria. Antibiotics are only effective against bacterial infections, and they will not work against viral infections, such as the common cold or the flu.
Antibiotics are available by prescription only. They are not available over-the-counter, as they can be dangerous if they are not used properly. Antibiotics should only be used to treat bacterial infections that have been diagnosed by a doctor.