Vesicles are small, fluid-filled sacs that can appear on your skin. The fluid inside these vesicles may be clear, white, yellow, or mixed with blood.
Vesicles are also sometimes referred to as blisters or bullae, though there are slight size differences among them. Vesicles are typically about five to 10 millimeters in diameter. If the sacs become larger than that, they’re classified as blisters. If they have a diameter of at least half a centimeter, they’re known as bullae.
Vesicles develop when fluid becomes trapped under the epidermis, the top layer of your skin. A number of different health conditions can cause them. Some of these conditions are minor and don’t require medical attention. Others are more serious and can signal a complicated medical issue that needs ongoing treatment.
Minor causes of vesicles include:
- allergic reactions that cause skin irritation
- dermatitis or eczema
- contact dermatitis, such as from poison ivy or poison oak
- cold sores
You should see a doctor if your vesicles are a result of:
Vesicles are often easy to recognize. Most develop on the surface of the skin and cause it to swell with fluid. The skin around the vesicle keeps the fluid contained.
Most vesicles rupture easily and release the fluid onto the skin. When the fluid dries, it may turn yellow or crusty.
Conditions that produce symptoms similar to vesicles can include:
- staph infections
- skin nodules
- neurofibromas, or tumors that develop on the nerves
- infected hair follicles
When a rash appears in the same place as multiple vesicles, it’s known as a vesicular rash. Heat rashes are one type of vesicular rash, occurring mainly in folds of the skin or wherever clothing can cause friction. Infections, such as staph infections that have spread, can also cause vesicular rashes. Contact dermatitis is an extremely common cause of vesicular rash.
Vesicular rashes may spread quickly. In the case of bacterial infections, keep the rash clean to prevent it from spreading to other parts of the body.
You should always make an appointment with your doctor if you develop unexplained vesicles on your skin. During the visit, they’ll ask you about your recent health history and about any medical conditions that might be causing the vesicles.
They’ll also examine your skin. Your doctor may be able to diagnose the cause of your vesicles based on this information alone.
If your doctor is uncertain about the cause of your vesicles, they may recommend more tests. They may also take a sample of fluid or a biopsy of the skin tissue from the vesicle to send to a lab. The analysis of the sample will help them to confirm your diagnosis.
You should always talk with your doctor about the best treatment options to reduce your symptoms.
Treatment for your vesicles depends on the cause. Over-the-counter remedies may be enough to treat vesicles caused by allergic reaction, dermatitis, poison ivy, or cold sores. Many of these remedies are topical ointments that can soothe the skin. Antihistamines may be able to reduce allergy-related causes.
Vesicles can be accompanied by other serious symptoms, such as inflammation or infection. In these cases, your doctor may prescribe medications to treat the underlying causes.
For example, bullous pemphigoid — a type of autoimmune disorder that affects older adults — is typically treated with corticosteroids to help reduce inflammation and antibiotics to help prevent infection.
Bacterial infections are typically treated with oral antibiotics so as not to aggravate the vesicles.
Vesicles caused by eczema are often treated with topical medications, including retinoids and glucocorticoids.
Blisters or vesicles caused by burns will be treated with prescription burn creams. You may also be prescribed oral antibiotics to reduce the chance of infection.
Home treatments including alternative remedies can often be effective for treating vesicles or blisters.
To care for an open or torn vesicle, wash the area with soap and water or use hydrogen peroxide to clean the wound. You can use over-the-counter antibiotic ointment to prevent infection. Cover the area with a clean bandage to protect it.
Natural treatments for vesicles that haven’t been torn or drained include:
- aloe vera, which is soothing and has anti-inflammatory properties
- apple cider vinegar, which has anti-inflammatory and antibacterial properties to reduce swelling and help dry the vesicle out
- tea tree oil, which has antibacterial and astringent properties
Popping a vesicle isn’t typically advised. It can leave the area open to infection and make it take longer to heal. Unless the vesicle becomes large and exceptionally painful, leaving it alone is best.
Your outlook depends on the underlying cause. If your vesicles are caused by an allergic reaction or contact dermatitis, you will typically make a full recovery after treatment.
More serious cases of vesicles can be a result of your genetics or an infection with a virus, so the vesicles may reoccur throughout your life. Proper treatment may relieve your symptoms. However, if you have a chronic condition, the vesicles are likely to return.
If you know you have allergies, you can help prevent vesicles by avoiding your allergens. You should also take care not to share cups, straws, or lip products.
You can also avoid wearing tight-fitting clothing that rubs uncomfortably on the skin, especially in hot or damp weather. You should wear proper attire for sports or physical activity, such as socks with extra padding. Moisture-wicking clothing can also be helpful.
Keep your skin clean, maintain good hygiene, and avoid irritants that could aggravate your skin. Antibacterial soaps can help prevent vesicles from becoming infected (and infections from causing vesicles). Shower immediately after working out or coming into contact with a potential skin irritant.
In some instances, it may not be possible to prevent vesicles.
When to see a doctor
Most vesicles, blisters, and bullae can be treated with over-the-counter treatments and home remedies. In some cases, however, it’s a good idea to call your doctor.
If you experience a rapid spread of vesicles, especially with a rash, and symptoms such as shortness of breath, pain, or dizziness, you may be having an allergic reaction to medications. In these cases, you should seek immediate medical attention.