What is a blister?
A blister is a bubble on the skin
containing fluid. Blisters are often shaped like a circle. The fluid that forms below
the skin can be bloody or clear.
What causes blisters?
Injury, allergic reactions, immune diseases, or infections can cause blisters. These
(friction), such as from shoes rubbing against the skin
contagious skin infection (impetigo)
reactions such as poison ivy
blistering skin disease that often occurs in middle-aged and older adults
blistering autoimmune disorder that is more common in older adults (pemphigoid)
blistering autoimmune disorder linked to gluten sensitivity that often first appears
in adults between ages 30 and 50 (dermatitis herpetiformis)
infections such as chickenpox and herpes zoster
What are the symptoms of a blister?
Blisters caused by injury or rubbing
(friction) will appear in that one area as a bubble filled with either clear or bloody
liquid. Blisters that are due to another condition may appear in one area of your body.
Or they may be all over your body. Blisters may be painful or itchy. In some cases the
blister may be caused by something that affects the whole body, such as an infection.
Then you may also have whole-body symptoms such as fever, pain, or extreme tiredness
(fatigue). The symptoms of a blister may look like other skin conditions. Always see
your healthcare provider for a diagnosis.
How are blisters diagnosed?
Healthcare providers can often
diagnose blisters by looking at your skin. If your provider thinks you may have an
infection or a skin disorder, a blister biopsy may be done. A piece of the blister is
removed and checked under a microscope. Or a skin culture may be needed.
How are blisters treated?
Blisters often heal on their own without treatment. If needed, treatment will vary, depending on the cause. Some general guidelines for first aid may include:
Wash the area with soap and water.
cold or ice pack which may help reduce swelling and discomfort.
the area clean and dry. Don't burst or puncture the blister.
If the blister bursts, place a bandage or dressing on the area to keep it clean.
the area for signs of infection such as increased warmth, swelling, redness,
drainage, pus formation, or pain. If you notice any signs of infection, call your
healthcare provider. You may need antibiotics.
Key points about blisters
A blister is a bubble on the skin containing fluid.
Blisters are caused by injury, allergic reactions, or infections.
symptoms of a blister may look like other skin conditions.
If you have whole-body symptoms, such as a fever, talk with your healthcare provider.
Blisters often heal on their own.
It is important to keep the area clean and dry.
to help you get the most from a visit with your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember
what your provider tells you.
At the visit, write down the name of a new diagnosis, and any
new medicines, treatments, or tests. Also write down any new instructions your
provider gives you.
Know why a new medicine or treatment is prescribed, and how it
will help you. Also know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results
Know what to expect if you do not take the medicine or have the
test or procedure.
If you have a follow-up appointment, write down the date, time,
and purpose for that visit.
Know how you can contact your provider if you have questions.