Impetigo (Impetigo Contagiosa)

Medical Author:
Medical Editor:

Impetigo facts

  • Impetigo is a bacterial infection of the surface of the skin.
  • Impetigo is more common in children than in adults.
  • The two types of impetigo are non-bullous and bullous impetigo.
  • Impetigo is contagious and is caused by strains of both staph and strep bacteria.
  • Impetigo is not serious and is easy to treat with either prescription topical or oral antibiotics. Scarring is very rare.

What is impetigo? What causes impetigo?

Impetigo (pronounced im-puh-TIE-go) is a contagious, superficial infection of the skin caused by Staphylococcus (staph) and Streptococcus (strep) bacteria. Impetigo is more common in children (especially 2- to 5-year-olds) than in adults. Impetigo is most likely to occur in warm and humid environments and is most commonly spread by close contact (such as family members).

What are the types of impetigo, and what are impetigo symptoms and signs? What does impetigo look like?

There are two forms of impetigo:

  • Non-bullous impetigo: This is the more common form, caused by both staph and strep bacteria. This form initially presents as small red papules similar to insect bites. These lesions rapidly evolve to small blisters and then to pustules that finally scab over with a characteristic honey-colored crust. This entire process usually takes several days. These lesions often start around the nose and on the face, but less frequently they may also affect the arms and legs. At times, there may be swollen but non-tender lymph nodes (glands) nearby.
  • Bullous impetigo: This form of impetigo is caused only by staph bacteria. These bacteria produce a toxin that reduces cell-to-cell stickiness (adhesion) causing separation between the top skin layer (epidermis) and the lower layer (dermis). This leads to the formation of a blister. (The medical term for blister is bulla.) Bullae can appear in various skin areas, especially the buttocks and trunk. These blisters are fragile and contain a clear yellow-colored fluid. The bullae are delicate and often break and leave red, raw skin with a ragged edge. A dark crust will commonly develop during the final stages of development. With healing, this crust will resolve.
Medically Reviewed by a Doctor on 6/27/2014

Patient Comments

Viewers share their comments

Impetigo - Length Symptoms Lasted Question: How long did the symptoms of your impetigo last? Was there anything in particular that helped with pain/symptom relief?
Impetigo - Treatment Question: What was the treatment for your impetigo?
Impetigo - Causes Question: If known, what caused impetigo in you or your child?
Impetigo - Contagious Setting Question: Did someone in your household catch impetigo from a highly contagious setting? Share your experience.

Impetigo Treatment

Mupirocin (Bactroban, Bactroban Nasal, Centany)

For the treatment of impetigo, a small amount of the ointment is applied to the affected area, usually three times daily. The area may be covered with a sterile gauze dressing. If there is no improvement in 3-5 days, the physician should be contacted to re-examine the infected area. For other skin infections, the cream is applied to the affected area 3 times a day for 10 days, and the doctor should be contacted as well if there is no improvement after 3-5 days.

Picture of impetigo