What should you know about a black lump under the skin?

Its dark appearance may come from blood, pigment, a blocked or inflamed follicle, or a skin growth. Colour alone cannot identify the cause, especially because inflammation and skin cancers can look different across skin tones.

A tender lump that becomes warm, swollen, or drains pus may be an inflamed follicle or boil. A trapped collection of blood after a knock can look purple, brown, or black. Cysts and other benign growths can also become dark after irritation.

Basal cell carcinoma can present as a firm dark-brown or black growth in darker skin, although many dark lumps are not cancer. A clinician may use close examination and, when needed, a small skin sample to distinguish conditions that look alike.

Do not squeeze, cut, pierce, or apply strong bleaching products to the lump. Keep the area clean, avoid friction, and photograph it in consistent lighting with a ruler nearby. Note when it appeared and whether its size, colour, surface, tenderness, or drainage changes.

Arrange a routine dermatology visit for a persistent or unexplained lump. Treatment depends on the diagnosis: an infected lump, an inflamed cyst, and a suspicious growth need different care. A steroid injection into the skin is suitable for selected inflammatory lesions, not for every dark lump.

Seek prompt medical assessment if the lump grows, changes shape or colour, repeatedly crusts or bleeds, becomes an open sore, or does not heal. Also arrange review if it feels fixed or very firm, or if a new lump looks unlike your other marks.

Get urgent care for rapidly spreading redness, severe pain, fever, red streaks, or swelling near an eye. These features can accompany a spreading infection and should not be managed by squeezing the area at home.

Ask what diagnoses fit the lump's depth, texture, colour, and growth pattern; whether dermoscopy or a biopsy would clarify it; and what changes should bring you back sooner. Mention any injury, shaving, new skin product, drainage, previous similar lumps, or personal history of skin cancer.