What is a Blister?
A blister occurs on the bottom of the feet when a small pocket of fluid accumulates in the top layers of the skin. The fluid is usually comprised of serum or plasma. Blisters on your foot can be uncomfortable or even downright painful. Fortunately, in many cases blisters will heal without any special care or treatment.
What Causes Blisters on the Bottom of a Foot?
A blister is the result of damage to the upper layers of skin. The most common causes of blisters include:
- Rubbing or Friction: Walking long distances, wearing poorly fitting shoes, or repetitive motions can lead to blisters. Friction blisters are more likely to occur on moist skin in warm conditions.
- Extreme Temperatures: Frostbite and burns can both result in blisters.
- Chemical Exposure: Contact with certain solvents, detergents, or other chemicals can cause small, itchy blisters that are referred to as a form of contact dermatitis.
- Allergic Reactions: Insect stings or other allergic reactions may cause blisters.
- Pinching/Crushing: This can cause small vessels under the skin to burst. The blood can collect between the layers of skin creating a blister.
- Medical Conditions: Chicken pox, impetigo, herpes, and some forms of eczema can cause blisters.
Preventing Blisters on the Bottom of Your Feet
Oftentimes, blisters on the soles can be avoided by reducing any friction acting on the feet.
- You should make sure your shoes fit properly. Take the time to break in your shoes before going on long walks; this will help the shoes conform to your foot and reduce friction.
- You should change your socks frequently to keep your feet clean and dry.
- If an area of your foot starts to feel irritated, you can use bandages, tape, patches, or moleskin to prevent a blister from forming.
You should protect the blistered area with a loose bandage and avoid activities that can rub and irritate the area. Small moleskin pads can provide relief from blisters on weight-bearing areas on the bottom of the foot. These pads protect the affected area from further irritation, while leaving the skin over the blister open. You can also relieve discomfort by keeping small, itchy blisters cool, for example by taking a cold shower or applying an ice pack.
Recurrent blisters caused by bony prominences or deformities of the foot may require surgery to correct the underlying trigger.
Should I Pop a Blister?
As a general rule, you should not pop blisters to drain them yourself. This opens the wound to infection. However, if you do pop a blister, make sure you take the following precautions:
- Wash your hands and the blister thoroughly with soap and water.
- Try soaking the blister in warm water for 30 minutes.
- Clean the blister with rubbing alcohol or iodine.
- Rub the blister gently to see if it will pop.
- If you use a needle to pop the blister, make sure you disinfect the needle with alcohol first.
- Gently puncture the blister along the edge.
- Drain the fluid by pressing in the direction of the hole.
- Leave the flap of skin covering the blister unless it is dirty, torn, or contains pus.
- Clean the area again with soap and water.
- Cover the area with a little antibiotic ointment and a loose bandage.
- Change the bandage daily and whenever it becomes wet or dirty.
- Leave the area uncovered at night to allow the blister to dry.
You should never pop a blister if you have diabetes, cancer, HIV, or heart disease due to your increased risk of infection. You also should not pop blisters that result from contagious conditions like chicken pox, since this can pass the infection to others.
When to Consult a Doctor
You should see a doctor immediately if you see any signs of infection surrounding the blister. You may have an infection if:
- You notice warmth, redness, or swelling at the site of the blister.
- You observe redness that streaks or extends from the blister.
- You develop a fever.
- You develop general symptoms of illness such as nausea, vomiting, belly pain, or joint or muscle aches.
If you take care of your feet, they will take care of you. You can start by carefully selecting the right shoes and socks. This should keep the bottom of your feet happy and blister-free. If you are diabetic you should consult a doctor immediately if you develop blisters or any other type of injury to your foot. Even the smallest sore can turn into a dangerous ulceration for diabetics if not treated properly.