What should you know about impetigo white crust?

Impetigo is a contagious bacterial infection affecting the surface of the skin. It may begin with a small break, redness, oozing, or a shallow sore, then develop a coating as fluid dries. The coating can look pale, cream-coloured, or yellowish depending on the amount of dried fluid and the surrounding inflammation. A white crust is a description, not a diagnosis; eczema, irritation, and other skin infections can also crust. See [Crusting Skin](/symptoms/skin-crusting/) for broader context. Children and adults can spread impetigo through touching, scratching, shared towels, clothing, or bedding. Scratching can move infection to nearby skin, especially where there is already irritated skin such as [Atopic Dermatitis](/conditions/atopic-dermatitis/).

Arrange a clinical assessment if the sore is spreading, returning, painful, or not settling. Until then, wash hands after touching the area, keep the sore gently clean, avoid picking the crust, and cover it with a clean dressing when practical. Do not share towels, razors, pillowcases, or clothing, and launder items that contact the lesion. A clinician may recommend [Topical Antibiotic Therapy](/treatments/medical-dermatology/topical-antibiotic-therapy/) for a limited area or [Antibiotics For Skin Infection](/treatments/medical-dermatology/antibiotic-therapy-for-skin-infection/) when infection is more extensive or needs medicine by mouth. Use treatment exactly as prescribed and complete the advised course.

Seek prompt medical care if redness, warmth, swelling, tenderness, or drainage is expanding; if the sore is near an eye; or if you feel feverish or unwell. Urgent assessment is also sensible for rapidly worsening pain, marked swelling, or reduced ability to use the affected area. A baby, a person with a weakened immune system, or someone with diabetes may need earlier advice. Do not wait for the crust colour to change before seeking help when the skin is worsening.

Could this be impetigo or another cause of crusting? Is treatment needed on the skin or elsewhere? How should the area be cleaned and covered, and when can close contact or school return safely? What signs would mean the infection is spreading?