Impetigo is a common, contagious bacterial skin infection that most frequently affects young children, though it can occur in people of any age. It typically presents as sores and blisters, often around the nose and mouth, making it a visible and sometimes distressing condition. The duration of impetigo is profoundly influenced by whether appropriate medical treatment is sought and initiated promptly.
What Impetigo Is and Why It Needs Treatment
Impetigo is caused by bacteria, primarily Staphylococcus aureus or Streptococcus pyogenes, which invade the skin, often through a minor cut, scrape, or insect bite. It appears in two main forms. The non-bullous type is most common, characterized by small red sores that burst and leave a distinctive honey-colored crust. The less frequent bullous impetigo is marked by larger, fluid-filled blisters, typically caused exclusively by S. aureus.
Although the body’s immune system may eventually clear the infection, treatment is recommended to accelerate healing and, more significantly, to limit the spread to others. The bacteria are highly transmissible through direct contact with the sores or contaminated items like towels and clothing. Treating the infection quickly drastically reduces the period of contagiousness, which is a major factor in preventing widespread outbreaks. Seeking treatment also minimizes the rare, but serious, risk of complications, such as post-streptococcal glomerulonephritis, which can occur after a strep-based infection.
Healing Timelines With and Without Medication
The healing timeline for impetigo depends on the use of antibiotic medication. With appropriate treatment, the infection begins to clear rapidly, and the patient ceases to be contagious quickly. Most individuals are no longer considered contagious approximately 24 to 48 hours after starting a topical or oral antibiotic regimen.
The lesions will then begin to fade, with complete resolution typically occurring within seven to ten days of starting the medication. Even if the sores appear gone sooner, it remains important to complete the full course of antibiotics prescribed to ensure all bacteria are eradicated and prevent recurrence.
If impetigo is left untreated, the infection can persist for a much longer period. Without antibiotics, the condition may take two to three weeks, or longer, to resolve naturally. During this time, the sores remain active, meaning the person is contagious for several weeks, greatly increasing the likelihood of spreading the infection to close contacts. Delaying treatment also increases the chance of the infection spreading to other parts of the body through scratching or progressing into a more serious condition.
Specific Treatment Options for Faster Clearance
Medical intervention focuses on targeting the bacteria. For localized and milder cases, a topical antibiotic ointment is typically the first line of treatment. Medications such as Mupirocin or Retapamulin are applied directly to the sores multiple times a day for five to ten days.
Ensuring the efficacy of topical treatment requires gently cleaning the affected area before application. Soaking the crusted lesions with warm, soapy water helps remove the thick crusts. These crusts act as a barrier preventing the antibiotic from reaching the bacteria. Once removed, the ointment can be rubbed directly into the skin lesions, allowing it to begin killing the bacteria.
For more widespread infections, bullous impetigo, or when topical treatment proves ineffective, an oral antibiotic is usually prescribed. These medications may include drugs like Cephalexin or Dicloxacillin. The choice between topical and oral antibiotics is based on the severity and extent of the infection, with oral options reserved for substantial bacterial loads or deeper skin involvement. Patients must complete the entire course of oral medication, even after the sores have visibly healed, to prevent resistance and ensure the infection does not return.
Practical Steps to Prevent Spreading
While the infection is being treated, hygiene practices prevent the spread of bacteria. Frequent hand washing is necessary, especially after touching the infected sores or applying medication, to remove lingering bacteria. Sores should be kept covered with a clean, loose bandage or gauze whenever possible to create a physical barrier and minimize contact transmission.
Personal items that contact the sores must be managed carefully to avoid cross-contamination within a household. Sharing items must be avoided during the infectious period.
- Towels
- Washcloths
- Bedding
- Clothing that an infected person has used should be washed daily in hot water.
Trimming fingernails short limits the space where bacteria can accumulate, reducing the risk of scratching the lesions and spreading the infection. Children with impetigo should remain home from school or daycare until they have completed at least 24 hours of antibiotic treatment, or until all the sores are dry and crusted over.