What causes a small patch of skin to darken and start peeling, and what should be done about it?

Skin darkening in a localized area accompanied by peeling is usually caused by factors such as sun exposure, friction injury, post-inflammatory hyperpigmentation, tinea corporis (fungal infection), or psoriasis. Depending on the specific condition, patients may improve symptoms through general care, medications, or other treatments. Detailed analysis is as follows:

1. Sun Exposure

Ultraviolet radiation activates melanocytes while damaging the skin barrier, leading to dryness and peeling. Apply sunscreen and wear a sun hat when going outdoors. After sun exposure, use a cool compress with a damp towel and apply a moisturizing repair cream.

2. Friction Injury

Chronic friction causes thickening and shedding of the stratum corneum, with local inflammatory reactions resulting in pigment deposition. Switch to loose, soft clothing to avoid continuous friction on the affected area. Cleanse with warm water and apply a moisturizer to soften the keratinized skin.

3. Post-Inflammatory Hyperpigmentation

Following resolution of prior skin conditions such as eczema or dermatitis, increased melanocyte activity leads to dark spots, while impaired skin barrier function results in peeling. Strict sun protection is essential. Topical treatments such as hydroquinone cream, tretinoin cream, or urea-vitamin E cream may be used as directed by a physician.

4. Tinea Corporis (Ringworm)

Fungal infection of the skin triggers inflammation, causing both pigmentation changes and flaking. Keep the affected area dry and avoid scratching. Use topical antifungals such as terbinafine hydrochloride cream or ketoconazole cream, and take oral itraconazole capsules as prescribed.

5. Psoriasis

Immune dysfunction accelerates skin keratinization, resulting in red plaques and scaling, followed by post-inflammatory pigmentation. Avoid skin irritants. Topical treatments such as calcipotriol ointment or desonide cream, along with oral acitretin capsules, should be used under medical supervision.

In daily life, maintain adequate skin hydration and sun protection, and minimize friction and irritation. Eat a balanced diet rich in vitamins. If the darkened patch continues to expand, scaling worsens, or itching develops, seek timely medical evaluation for accurate diagnosis and treatment.