What Is Impetigo?

Medically Reviewed by Jabeen Begum, MD on October 31, 2023
9 min read

Impetigo is a common bacterial skin infection that spreads easily. It causes itchy sores or blisters to form on exposed skin, commonly around the nose or mouth. Impetigo is seen most often in babies and young kids, but you can get it at any age. The condition happens more often in the summer. Antibiotic treatment can help get rid of it. 

Impetigo looks different based on the type you get and the color of your skin. But there are three main types, including: 

  • Non-bullous impetigo. This is the most common type. It causes tiny blisters to form around the nose and mouth that itch but usually aren’t that painful. These blisters eventually break open and ooze pus and fluid, leaving behind crusty yellow or golden scabs on your skin. This dry crust becomes a mark on the skin that fades over time without leaving a scar. Fever and swollen glands can develop in more serious cases.
  • Bullous impetigo. You’ll get large fluid-filled blisters with this kind. They appear from the neck to the waist, but can also show on the arms and legs. The blisters spread quickly and burst after several days, leaving a crust that goes away without scarring. The area around the blisters may cause pain and itchiness. High temperatures and swollen glands are more common with this type of impetigo.
  • Ecthyma. If impetigo goes untreated, it can develop into this form. Ecthyma is more serious because it goes deeper into the skin. It causes sores that are painful and filled with liquid or pus that lead to ulcers. Crust and redness develop around the sore. With this form, scars can develop, because the sores are set in the skin.

For all of the types of impetigo, you should avoid touching or scratching the affected areas. The infection can spread to other parts of your body or to other people.

You’re most likely to get an impetigo infection around your nose and mouth or somewhere else on your face, but impetigo sores can appear anywhere on your skin on the body. Children tend to get them on their face. Sometimes they show up in the middle of your body (between your belly and neck) or on your arms or legs.

Depending on your skin tone, impetigo may look different, but symptoms may include:  

  • Impetigo rash. The infected areas range from dime to quarter size. They start as tiny clusters of blisters that break open and reveal moist, red, raw skin that may look like other kinds of rashes at first. But after a few days, you’ll get a grainy, golden crust that gradually spreads at the edges.

Impetigo diaper rash happens when babies or young kids get an infection in moist spots under or around their diaper area.

An impetigo rash may look red on lighter skin tones. The sores may be harder to notice right away on brown or darker skin, but they might be purple or grayish in color.

  • Impetigo blisters. Before you develop a crusty yellow or golden scab, you may get itchy sores that hurt and burst and leak fluid or pus for a few days. The blisters caused by bullous impetigo tend to be larger and stay longer than the kind from non-bullous impetigo. 

 

The most common cause of impetigo is bacteria called Staphylococcus aureus. Another bacteria source is group A streptococcus. You get impetigo when your immune system doesn’t fight off an infection from certain bacteria.

These bacteria lurk everywhere. The most common way for your child to get impetigo is when they have contact with someone who has the infection, such as from playing contact sports like wrestling. It's especially easy to pick it up if your kid has an open wound or a fresh scratch.

 

 

 

In addition to being able to get impetigo from your skin's contact with bacteria, there are certain things that increase the chances you’ll get an infection, including:  

  • Younger age. It shows up most often in kids ages 2 to 5. Experts think that’s because a child’s immune system hasn’t fully developed yet. 
  • Living in a certain climate. Impetigo is more common when it’s warm and humid outside. 
  • Open wounds. Germs can get inside your skin easier when it’s already broken.
  • Other skin problems. People who have skin problems, fungal infections, or other skin conditions – like scabies, atopic dermatitis, eczema, body lice, or insect bites , – may have a harder time guarding against impetigo. 
  • Crowded spaces. Germs spread easier in places where people are in close contact with one another, such as schools or day care centers. If you share clothes, bedding, towels, or other objects with someone with the infection, you can catch impetigo.

Health conditions or medical treatment that weaken your immune system can also raise your risk of impetigo, including: 

  • Cancer treatment (chemotherapy)
  • Diabetes
  • Liver damage
  • HIV or AIDS infection
  • Kidney problems
  • Drug use through a vein in your arm
  • Treatment with dialysis
  • IV (intravenous) drug use

If you’re already at a higher risk of impetigo, you may be more likely to get an infection if you don’t wash your hands, body, or face very often. 

Children are also at risk of re-infection, as they may scratch and open their scabbing.

If impetigo goes untreated, there's a greater risk of complications.

Impetigo rarely causes serious or long-lasting health issues, but complications do happen. These problems are more likely to pop up if your impetigo is severe and goes untreated, but most impetigo complications clear up with antibiotics. 

Impetigo complications may include: 

Cellulitis. This is when the infection goes deeper into your skin. The area may get red, warm, swollen, or painful. You may also get other signs of infection, including fever, chills, or generally feeling unwell. Untreated cellulitis can be fatal. 

Guttate psoriasis. This is a non-infectious skin condition that can show up after a bacterial infection. You may get red, scaly patches on your arms, chest, legs, or scalp. It may go away without treatment in a few weeks, but tell your doctor about it. Creams may help.  

Scarring. Impetigo blisters and rashes typically don't damage your skin permanently. Scars are more likely to develop from ecthyma or intense scratching, so try not to touch your sores even if they’re really itchy. 

Post-streptococcal glomerulonephritis. Rarely, impetigo can infect the tiny blood vessels in your kidneys. This can be fatal. Get medical help right away if you notice symptoms such as dark or bloody urine; swelling of your belly, face, eyes, feet, or ankles; or if you pee a lot less. 

Septicemia. This is a bacterial infection in your blood. It can be life-threatening and needs fast antibiotic treatment. Go to the hospital if you or a loved one has impetigo with symptoms such as diarrhea, a high fever, fast breathing, dizziness, or throwing up.

Staphylococcal scalded skin syndrome. One of the bacteria that causes impetigo can send out a kind of poison that causes your skin to blister. It may hurt, turn red, or start to peel off. You’ll need treatment right away with antibiotics through a vein in your arm.   

Scarlet fever. See your doctor if you notice a faint, pink rash across your body. This bacterial infection usually isn’t serious, but you could spread it to others if you don’t take antibiotics to clear it up.  

To diagnose impetigo, your doctor will ask about your symptoms and check for sores and blisters on your face and other areas of your body. Lab tests usually aren't needed. 

Some bacteria are resistant to certain antibiotics. You’re more likely to need extra lab work if your infection doesn’t get better with the first treatment you try. The doctor may take a sample of liquid from one of the sores to see which antibiotic might work the best. 

If you get impetigo a lot, the doctor may swab the inside of your nose and send the sample to a lab. They’re checking to see if you have bacteria in your nostrils causing repeat infections. 

These infections usually aren’t serious and may go away on their own within a few weeks, but doctors usually recommend antibiotic treatment for impetigo. 

There’s no guaranteed way to get rid of impetigo overnight, but antibiotics can help your skin heal faster (usually within 7 to 10 days) and lessen the chances you’ll spread the bacteria to someone else. 

Antibiotics to treat impetigo include: 

Impetigo cream. If you have only a few sores, your doctor may suggest you put over-the-counter or prescription antibiotic ointment or cream directly on your skin. They’ll let you know exactly how to use this topical treatment and for how long.  

To use antibiotic cream or ointment for impetigo, here are some things your doctor might suggest: 

  • Wash the affected area with soap and water to clear away crusted skin. 
  • Apply the antibiotic cream three or four times a day for 5 to 7 days.
  • Wash your hands before and after you touch your skin.
  • Cover the infected area loosely with a bandage, if possible. 

If your symptoms don’t start to improve within a few days, tell your doctor. They may need to switch you to a different kind of antibiotic or another type of medicine. 

Impetigo antibiotics by mouth. You may need to take antibiotic pills or liquid for 7 to 10 days if your impetigo is serious or covers a big area. Your doctor may switch you to oral antibiotics if skin cream or ointments don’t help. 

Use impetigo antibiotics for as many days as your doctor tells you to, even if your skin gets better before you run out of medicine. Your infection is more likely to come back if you stop treatment early. 

Check in with your doctor or dermatologist if you suspect impetigo. They can take a look at your skin to figure out what’s going on and find the best way to treat your blisters and sores. 

Tell the doctor if you or your child gets a fever along with skin problems. And let them know if the infection gets worse or if impetigo is not healing with antibiotics within a week of starting treatment.

If you keep getting impetigo rashes or bullous impetigo, your doctor may run some tests to see why your skin can’t fight off the bacteria.

You may not be able to avoid exposure to the bacteria that cause impetigo, but you can lessen the chances of spreading the infection to other people or other parts of your body.

How to stop impetigo from spreading. Talk to your doctor about how to care for your skin, and use antibiotics or other impetigo treatment exactly as prescribed. 

You should also: 

  • Clean your sores with soap and water.
  • Wash your hands often. 
  • Keep the sores covered with a bandage until they heal, if possible. 
  • Wash or disinfect toys touched by someone with impetigo. 
  • Use hot water to wash sheets, towels, clothing, or bedding used by someone with impetigo. 
  • Follow up with your doctor if your sores don’t get better with treatment. 

Until your infection clears up or your doctor gives you the OK, here are some things to remember: 

  • Don’t touch or scratch your sores (or let other people touch your infected skin). 
  • Don’t have close contact with other people, especially babies or young kids. 
  • Don’t go to work, school, sports practice, day care centers, or to the gym.
  • Don’t share unwashed clothes, linens, or towels.