first aid

What is a blood blister?

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A blood blister forms if the skin has been crushed or pinched, but can also develop due to repetitive friction. It is important to note that blisters develop if the upper skin layers separate and fluid builds up in the layers that separated, resulting to a bubble.

This type of blister contains some blood inside the skin bubble due to damage to the tiny blood vessels in the skin. Generally, these blisters do not necessitate specific treatment and settle after some time. Nevertheless, there are certain measures that can be done to lessen the discomfort and protect the site as it heals.

Caring for a blood blister

Application of ice

An initial measure is to apply ice on the site right away to stop the bleeding by narrowing of the damaged blood vessels.

Accidentally striking the finger with a hand tool or slamming the finger in a door are usual ways for a blood blister to form. An initial measure is to apply ice on the site right away to stop the bleeding by narrowing of the damaged blood vessels.

Even though the clotting system of the body puts an end to the bleeding rapidly even without using ice, applying one can help relieve the acute pain due to the injury.


Even though it might be tempting to break open or pop a blood blister, it should be left alone. This is vital if the individual has diabetes or other health condition that deteriorates the immune system.

The unbroken surface of the blister known as the roof protects the site from infection. Generally, you should shield the blister from rupturing if it forms in a site that is prone to being rubbed or bumped. Depending on the size and site of the blood blister, you can utilize a loose adhesive bandage, blister bandage or even a moleskin with a hole in the middle to expose the blister to open air.

Caring for an open blister

In case the blister already ruptured, cleanse the site using water and soap. Leave the roof of the blister instead of trimming it away since the skin under it is highly sensitive and prone to infection.

After cleansing, cover the area loosely using bandage to keep it protected. An over-the-counter antibiotic ointment can be used.

How long does it heal?

A blood blister generally recuperates within 1-2 weeks. During this time frame, make sure that the site is kept clean and protected.

Cleanse using water and soap as needed and change the protective covering to keep the area dry and clean.

In case at some point the roof comes off, do not be worried. Keep the site clean, dry and protected. The individual should avoid activities, clothing or shoes that can irritate the recuperating blister.

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