Mupirocin is an antibiotic Overview of Antibiotics Antibiotics are drugs used to treat bacterial infections. They are ineffective against viral infections and most other infections. Antibiotics either kill microorganisms or stop them from reproducing... read more that is used to treat impetigo Impetigo and Ecthyma Impetigo is a superficial skin infection, caused by Staphylococcus aureus, Streptococcus pyogenes, or both, that leads to the formation of scabby, yellow-crusted sores and, sometimes... read more 
and some other bacterial skin infections Overview of Bacterial Skin Infections The skin provides a remarkably good barrier against bacterial infections. Although many bacteria come in contact with or reside on the skin, they are normally unable to establish an infection... read more and to eliminate staphylococci from the nose Prevention Staphylococcus aureus is the most dangerous of all of the many common staphylococcal bacteria. These gram-positive, sphere-shaped (coccal) bacteria (see figure How Bacteria Shape Up)... read more 
. Mupirocin works by interfering with the bacteria's production of the proteins it needs to grow and multiply.
It is available only as an ointment.
Health care practitioners may recommend applying the antibiotic mupirocin inside the nostrils to eliminate staphylococci from the nose. However, because overusing mupirocin can lead to mupirocin resistance, this antibiotic is used only when people are likely to get an infection. For example, it is given to people before certain operations or to people who live in a household in which the skin infection is spreading.
Some common side effects of mupirocin are itching and burning.
