Impetigo is a skin infection caused by bacteria. It is more common in children than in adults. Impetigo is usually a mild infection but it can spread and cause serious illness if it is not treated.
Impetigo is caused by bacteria. The 2 types of bacteria that cause the infection are called Staphylococcus aureus and Streptococcus pyogenes (Group A streptococcus). These bacteria can live on your skin without hurting you. However, if they get into a wound, they may cause an infection.
Impetigo is more likely to happen if you have a chronic skin condition like eczema, or when you have a scratch, scrape, insect bite, or other skin irritation that causes a break in the skin. Impetigo is more common when it is hot and humid. It is very contagious. Physical contact, including scratching, can spread the infection to other parts of the body or to other people. It can also be spread by contaminated clothing, athletic equipment, towels, bed linen, and toys.
Impetigo can occur on any area of skin. It often appears on the face between the upper lip and nose. The infection begins as small blisters. The blisters form pus inside and then break open. The pus from the blisters dries as a gold or yellow-colored crust. The blisters or sores are painless.
Your healthcare provider will look at the blisters or sores on your skin. Impetigo can often be diagnosed without any tests. In some cases your provider may remove a small amount of pus from one of the sores for tests to identify the bacteria and find which antibiotics will work best to treat the infection.
The treatment depends on your age and the severity and type of infection that you have. If the infection is mild, all you may need to do is keep your skin clean so the infection can heal on its own. Your healthcare provider may prescribe an antibiotic ointment to put on your skin.
You may need to put some of the antibiotic ointment inside your nose. Some people carry the bacteria inside their nose and the infection may come back if the nose is not treated. Ask your healthcare provider if this applies to you.
For larger or more serious infections, your provider may prescribe an oral antibiotic medicine or give you a shot of antibiotic medicine.
The sores should begin to heal within 2 to 5 days after you start using an antibiotic. If you are taking an oral antibiotic, the infection usually stops being contagious after 24 hours of treatment. If you are using an antibiotic ointment instead, the sores will no longer be contagious when they stop oozing and are drying up.
Follow these tips to ease the discomfort of impetigo:
If your provider prescribed an antibiotic ointment, gently pat your skin dry after you wash the infected area and put a thin layer of antibiotic ointment on it with a cotton swab (Q-tip®). Do not touch the tube of antibiotic ointment to the infected area. Also do not touch the ointment tube with the used cotton swab. If you need more ointment, use a new cotton swab. Do not use the ointment more often than directed. Wash your hands thoroughly after using this medicine.
If your provider prescribed an antibiotic to take by mouth, take all of it exactly as directed by your provider. If you stop taking the medicine too soon, the infection may not be completely gone yet or it may return.
Call your healthcare provider if:
