What are Blisters
Blister is a raised bubble of skin filled with liquid. Blisters often develop in an area of the skin that repeatedly rubs or presses against another surface (friction blister).
Friction blisters can occur on any part of the body, but they usually develop on the hands or feet. Long-term pressure on the same area of the skin can also lead to areas of hardened skin (calluses).
What are the causes?
A blister can be caused by:
- An injury.
- A burn.
- An allergic reaction.
- An infection.
- Exposure to irritating chemicals.
- Friction, especially in an area with a lot of heat and moisture.
Friction blisters often result from:
- Repetitive activities.
- Using tools and doing other activities without wearing gloves.
- Shoes that are too tight or too loose.
What are the signs or symptoms?
A blister is often round and looks like a bump. It may:
- Be painful to the touch.
Before a blister forms, the skin may:
- Become red.
- Feel warm.
- Be painful to the touch.
How is this diagnosed?
A blister is diagnosed with a physical exam.
How is this treated?
Treatment usually involves protecting the area where the blister has formed until the skin has healed. Other treatments may include:
- A bandage (dressing) to cover the blister.
- Extra padding around and over the blister, so that it does not rub on anything.
- Antibiotic ointment.
Most blisters break open, dry up, and go away on their own within 1–2 weeks. Blisters that are very painful may be drained before they break open on their own. If the blister is large or painful, it can be drained by:
- Sterilizing a small needle with rubbing alcohol.
- Washing your hands with soap and water.
- Inserting the needle in the edge of the blister to make a small hole. Some fluid will drain out of the hole. Let the top or roof of the blister stay in place. This helps the skin heal.
- Washing the blister with mild soap and water.
- Covering the blister with antibiotic ointment, if prescribed by your health care provider, and a dressing.
Some blisters may need to be drained by a health care provider.
Follow these instructions at home:
- Protect the area where the blister has formed as told by your health care provider.
- Keep your blister clean and dry. This helps to prevent infection.
- Do notpop your blister. This can cause infection.
If you were prescribed an antibiotic, use it as told by your health care provider. Do not stop using the antibiotic even if your condition improves.
- Wear different shoes until the blister heals.
- Avoid the activity that caused the blister until your blister heals.
your blister every day for signs of infection. Check for:
- More redness, swelling, or pain.
- More fluid or blood.
- Pus or a bad smell.
- The blister getting better and then getting worse.
How is this prevented?
Taking these steps can help to prevent blisters that are caused by friction. Make sure you:
- Wear comfortable shoes that fit well.
- Always wear socks with shoes.
- Wear extra socks or use tape, bandages, or pads over blister-prone areas as needed. You may also apply petroleum jelly under bandages in blister-prone areas.
- Wear protective gear, such as gloves, when participating in sports or activities that can cause blisters.
- Wear loose-fitting, moisture-wicking clothes when participating in sports or activities.
- Use powders as needed to keep your feet dry.
Contact a health care provider if:
- You have more redness, swelling, or pain around your blister.
- You have more fluid or blood coming from your blister.
- Your blister feels warm to the touch.
- You have pus or a bad smell coming from your blister.
- You have a fever or chills.
- Your blister gets better and then it gets worse.