What is a blood blister?

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A blood blister is a piece of elevated skin with blood within. In most cases, it is relatively harmless and subsides on its own after a few weeks without any form of treatment.

What are the indications?

A blood blister strikingly resembles a friction blister. A blister varies in size and appear as a pocket of elevated skin. The presence of blood within is due to the broken blood vessels that mixes with the clear fluid.

The blood inside might be reddish or even purple or black in color. Typically, fresh blisters appear red and turn into a deeper shade over time.

The usual sites where a blood blister might form include:

  • Feet
  • Mouth
  • Hands
  • Near the joints
  • Bony areas such as the toes, heels or balls of the feet

One might also form if the skin has been pinched but did not break open.

blood-blister
A blood blister is usually left alone to allow it to recuperate, typically within 1-2 weeks.

When to consult a doctor

Generally, one blood blister is not an issue to be worried about. It is usually caused by rubbing of the skin repeatedly or being pinched by the door.

There are instances though that necessitates an assessment by a doctor such as:

  • There are signs of infection such as red-colored lines radiating away from the blister or warmth.
  • Blister forms for no reason.
  • There is difficulty in walking or using the hands
  • Several blisters form on the skin with an unknown cause
  • Recurrent blisters
  • A blister forms on the eyelid or in the mouth
  • Blister is due to a burn or an allergic reaction

Management of a blood blister

A blood blister is usually left alone to allow it to recuperate, typically within 1-2 weeks. The healing process takes place since new skin forms beneath the elevated layer of the blister. Over a span of days or weeks, the fluid in the blister eventually dries up.

Make sure that the blood blister is protected while it heals. It can be covered by a protective layer such as a bandage. In case there is discomfort, apply an ice pack wrapped with a clean cloth or towel. In some cases, pain medications can be given to lessen the pain.

Opening the blister should not be done. Remember that the elevated skin protects against the entry of bacteria. On the other hand, a doctor should be consulted if pressure from the blood blister is painful enough since it might require drainage.

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