A blister is a bubble of fluid which is found beneath the outer layer of skin. The fluid can be transparent or filled with blood or pus.
What is the cause of a blister?
There are many possible causes of blisters present, including a burn, disease, an allergic reaction, or rubbing of your skin against something.
Blisters can also be caused by your skin rubbing against something, like tools that you are using or shoes that don’t fit well are called friction blisters.
Friction blisters generally occurs when you start a new sport, exercise program, or sport season when you wear new shoes or when the weather is hot and humid.
How is blister diagnosed?
Your doctor will examine you and ask about your symptoms, activities, and medical history.
Follow these guidelines to have less rubbing of your skin:
- Make sure that your shoes fit well
- Don't wear wet shoes
- Wear 2 pairs of socks to protect your feet
- Wear gloves to protect your hands
- Put Vaseline on spots that tend to rub, or use a foot powder
- Put athletic tape or a bandage over sore spots
What are the symptoms of a blister?
When the skin gets irritated and fluid is collected beneath the outer layer of skin. This can be painful. The surrounding area around the blister may be red, sore, or swollen. Blisters can be very small or quite large.
Most blisters are filled with transparent liquid. If the liquid in a friction blister is bloody, it generally means that a lot of force has caused the blister.
If a blister is filled with pus, it may be infected. Infected blisters are very painful. They may be swollen and feel warm to the touch. You may even have a fever.
How is blister treated?
It’s best to leave most of the small blisters alone. Keep them clean and covered with an antibiotic ointment and a bandage. Put a little ointment around the blister or the part of a shoe that causes the irritation so there is less rubbing.
If possible, don’t wear the shoe that is causing the blister. Wear heavier socks to cushion the blister. Wear gloves if the blisters are on your hands.
You can also buy moleskin at a chemist store to save the blister. Cut a piece of moleskin that is bigger than the blister and make a hole in the center. Then put the moleskin on your skin with the hole over the blister. Cover the moleskin with a bandage.
Generally, blisters drain by themselves and last about 3 to 7 days. The skin that is covering the blister helps protect you from an infection.
Leave it in place until it is very dry and the underlying skin has become tough and painless. Then you can trim off the layer of dry skin with a clean pair of scissors.
Large blisters may need to be drained with a sterile needle. Talk to your healthcare provider about this.
If a blister gets infected, you need to see your doctor. Your provider may prescribe an antibiotic for the infection.