BLISTERS
A blister is a bubble of fluid under the skin that is caused by a skin reaction to irritation, injury, allergy, disease, infection or medication. The fluid inside a blister is called serum, a clear, watery liquid that leaks from surrounding tissues. If the blister is left unopened, the serum can provide natural protection for the skin beneath it. A blood blister is filled with blood, rather than clear fluid.
There are numerous causes of blisters, including:
 | Irritation — Blisters can be caused by physical factors that irritate the skin, such as: friction (rubbing the skin), irritating chemicals, or extreme cold or heat. For example, blisters on the feet can result from shoes that are either generally too tight or rub on the skin in one particular area. Blisters also can be due to an irritant. for example, contact dermatitis is a localized skin reaction due to some type of chemical irritant. Exposure to extreme temperatures can also cause blisters. For example, intense cold can trigger frostbite, which often produces blisters once the affected skin is re-warmed. Also, any type of burn, even sunburn, can produce blistering. Blisters caused by friction or burns are generally painful, while those resulting from eczema (also known as dermatitis) can be accompanied by redness, severe itching and small bumps on the affected skin. |
| Allergies — Allergic contact dermatitis, a form of dermatitis or eczema, is caused by an allergy to a chemical. A common example is contact with certain plants such as poison ivy, poison oak and poison sumac. |
| Infections — Infections that cause blisters include athlete's foot, which is a fungus infection that can cause small blisters on the feet. When blisters are caused by an infection, the associated symptoms vary depending on the type of infection. |
| Skin diseases — Numerous skin diseases cause blisters. When blisters are caused by a skin disease, the associated symptoms vary depending on the type of disease. |
| Medications — Many medications, can cause mild blistering skin reactions. Others can increase the risk of blistering sunburn by increasing the skin's sensitivity to sunlight. |
Symptoms
In general, blisters are round or oval bubbles of serum under the skin that may be painful or itchy, or they may cause no symptoms. Different causes have different associated symptoms.
Diagnosis
If the cause is not obvious (that is, there is no history of a local irritation, frostbite or burn), your doctor may ask about your family history and your personal medical history, including any allergies you have and any medications you are taking (including over-the-counter medications). You also may be asked about any recent exposure to irritating chemicals or allergens.
Your doctor often can diagnose the cause of your blisters simply by their appearance and your history. He/she will perform a complete physical examination; look at the size, shape, color and location of the blister(s); and ask you about any accompanying symptoms.
Duration
The duration of blisters varies widely depending on their cause. For example, blisters caused by irritation generally go away on their own within a few days, while those triggered by infections and skin diseases can remain for weeks or months.
Prevention
There are many simple strategies to prevent blisters caused by skin irritation. You can begin by wearing comfortable shoes that fit well, together with socks that cushion the feet and absorb sweat. Also, apply sunscreen to protect your skin from sunburn. Be particularly vigilant about avoiding sun exposure if you are taking medications that are known to cause sun sensitivity. During cold months, use warm mittens, hats and heavy socks to protect your skin against freezing temperatures and chilling winds.
Treatment
In general, it is best to leave blisters alone. Because the blister protects the underlying skin, breaking blisters open can increase the chance of infection. Protect blisters with a bandage and cover them until they heal on their own. The blister will be re-absorbed and flatten naturally. If a blister breaks, wash the area with soap and water, then apply a bandage. If a blister is large or painful, your doctor may drain it and apply an antibacterial cream to prevent infection.
If you are experiencing any of these signs or symptoms, call today for an appointment.