When to worry about discoloured nails with a bruised nail

A blow, trapped pressure, or crush injury can cause blood to collect beneath the nail. The nail may look red, purple, brown, or nearly black. Discolouration is a common presentation of Bruised Nail. As the nail grows, the marked area should gradually move toward the tip rather than remain fixed at its original position.

Protect the finger or toe from another impact, keep the nail clean and dry, and use a cool pack wrapped in cloth for short periods during the early discomfort. Do not pierce, drill, or pull off the nail yourself. A clinician can decide whether pressure needs releasing and whether the nail bed or bone may also be injured.

Arrange prompt assessment if pain is strong or worsening, the nail is lifting, the finger or toe looks bent, movement is difficult, or bleeding will not stop. Get medical advice if redness, warmth, swelling, pus, fever, or a red streak develops. A dark mark without a clear injury, or colour that does not grow out with the nail, also deserves examination.

Ask whether the nail bed needs examination, whether pressure should be relieved, how to protect the nail while it grows, and which changes would suggest infection or a deeper injury.