A vesicle is a small fluid-filled blister.
A vesicle is small — it may be as tiny as the top of a pin or up to 5 or 10 millimeters wide.
In many cases, vesicles break easily and release their fluid onto the skin. When this fluid dries, yellow crusts may remain on the skin surface.
Many diseases and conditions can cause vesicles. Common examples include:
- Allergic reactions to drugs
- Atopic dermatitis (
- Autoimmune disorders such as bullous pemphigoid or pemphigus
- Blistering skin diseases including
porphyriacutanea tarda and dermatitis herpetiformis Chicken pox Contact dermatitis(may be caused by poison ivy)
- Herpes simplex (cold sores,
genital herpes) Herpes zoster(shingles) Impetigo
It is best to have your health care provider examine any skin rashes, including vesicles.
Over-the-counter treatments are available for certain conditions that cause vesicles, including poison ivy and cold sores.
When to contact a medical professional
Call your doctor if you have any unexplained blisters on your skin.
What to Expect at Your Office Visit
Your doctor will look at your skin. Some vesicules can be diagnosed simply by how they look.
In many cases, however, additional tests are needed. The fluid inside a blister may be sent to a lab for closer examination. In particularly difficult cases, a skin biopsy may be needed to make or confirm a diagnosis.