What should you know about dark crusty spots on skin?

A crust forms when fluid, blood, or skin debris dries on the surface. This can follow a scratched pimple, acne, folliculitis, an ingrown hair, or irritation from shaving or a product. Dark color may reflect dried blood, deeper skin tone, or pigment left after inflammation. Crusting around the mouth can occur with perioral dermatitis, while facial flushing and sensitivity may accompany rosacea. Appearance alone cannot confirm the cause.

Wash gently with lukewarm water and a mild cleanser, pat dry, and avoid picking or peeling the crust. Do not apply strong acids, steroid creams, or antibiotic products without advice, especially on the face. Protect exposed skin from sunlight because inflammation can leave darker marks. If there are repeated bumps after shaving, change the hair-removal technique and seek advice about the underlying follicle problem. Selected acne-related inflammation may have treatment options such as LED light therapy.

Arrange a prompt skin examination if the crust keeps returning, fails to heal, grows, changes shape or color, bleeds without clear injury, or sits over a firm lump. Seek earlier care for spreading redness, warmth, swelling, pus, increasing pain, or fever. Rapid change, severe tenderness, or a lesion near the eye warrants urgent medical advice.

Could this be a healing pimple, folliculitis, irritation, or another lesion? Should it be examined or tested? What cleansing and treatment plan is appropriate, and what change should prompt an earlier review?