Impetigo is a common, highly contagious bacterial skin infection that manifests as red sores that quickly crust over with a characteristic honey-colored appearance. While true, deep scarring that alters the skin’s texture is rare with typical impetigo, temporary skin discoloration after the infection clears is a common part of the healing process. These temporary marks are not permanent scars and will fade over time, though the duration varies widely.
Understanding Lingering Skin Marks
The marks left behind after an impetigo lesion heals are usually discoloration, not structural scars. A true scar involves a permanent change in skin texture, such as a raised or depressed area, resulting from damage extending into the deeper layer of skin called the dermis. The most common aftermath of superficial impetigo is a flat change in color, known as post-inflammatory hyperpigmentation (PIH) or, less commonly, hypopigmentation.
Post-inflammatory hyperpigmentation appears as a flat spot darker than the surrounding skin, ranging from tan to dark brown or black. This darkening occurs because the inflammation triggers skin cells to produce excess melanin, the pigment responsible for skin color. PIH is often more persistent in individuals with naturally darker skin tones due to the increased reactivity of their pigment-producing cells.
Less frequently, the healing process results in post-inflammatory hypopigmentation, where the affected area appears lighter than the surrounding skin. Both hyperpigmentation and hypopigmentation are color changes residing in the epidermis or upper dermis. Since they do not represent deep structural damage, these marks are temporary and will eventually resolve as the skin naturally renews itself.
Variables Affecting Mark Fading
The time it takes for these lingering skin marks to disappear is highly variable. For many, the reddish or pink mark left after the crust falls off fades completely within a few weeks. However, hyperpigmented spots can take much longer to fully resolve, sometimes persisting for several months or even a year.
Factors Influencing Fading Time
- Skin tone: Darker skin types often experience more intense and prolonged PIH.
- Infection severity: Superficial non-bullous impetigo is less likely to leave lasting marks than the deeper infection known as ecthyma.
- Sun exposure: Ultraviolet (UV) light stimulates melanin production and darkens existing PIH, significantly delaying the fading process.
- Trauma: Scratching or picking at the sores increases the inflammatory response, leading to greater melanin production and a longer-lasting PIH mark.
Accelerating the Fading Process
While post-inflammatory marks will often fade on their own, specific strategies can accelerate this natural process. The most effective action is strict sun protection. Applying a broad-spectrum sunscreen with a high Sun Protection Factor (SPF) daily is essential to shield the healing skin from UV radiation, which aggravates hyperpigmentation.
Certain over-the-counter topical ingredients help speed up the turnover of pigmented skin cells. Ingredients like niacinamide (Vitamin B3) and Vitamin C work to interrupt the pigment production pathway and provide antioxidant benefits. Mild chemical exfoliants, such as alpha hydroxy acids like glycolic or lactic acid, can gently remove the pigmented surface cells, gradually lightening the mark.
For particularly stubborn marks, professional help from a dermatologist may be necessary. Prescription-strength treatments like retinoids, which increase skin cell turnover, or depigmenting agents like hydroquinone, can lighten the spots. In-office procedures such as chemical peels or certain laser treatments target and break down excess melanin, offering a faster resolution for persistent PIH.
Avoiding Severe Skin Damage
Preventing a true scar requires halting the infection quickly and preventing deep tissue injury. Impetigo is typically superficial, affecting only the outermost layers of the skin, which is why it usually heals without permanent scarring. The infection must be treated promptly with appropriate topical or oral antibiotics to stop the bacteria from causing deeper tissue damage.
The most common way a superficial infection progresses to a deeper, scar-forming wound is through physical trauma. Scratching or forcefully removing the crusted sores can extend the infection into the dermis, potentially leading to ecthyma. Ecthyma involves painful, deep sores that result in tissue loss and are the form of impetigo most likely to leave a permanent scar.
It is important to manage the itchiness associated with the healing sores, often by keeping fingernails trimmed and the area clean. Allowing the crusts to fall off naturally protects the delicate new skin underneath, ensuring the healing process remains confined to the surface layers.