Facts About A Vesicular Rash

Though it sounds ominous, it is likely that just about everyone has at one point in their life had a vesicular rash; it just may have been known by another name.  It is important for individuals to know what it is and what is causing it, however, in order to properly treat the particular condition.


The term “vesicular” pertains to any air or fluid filled sac, cyst or vacuole on the body; in other words, a blister or pimple.  Since blisters or pimples are symptoms of numerous different conditions, an individual who is diagnosed with a vesicular rash could be suffering from something as simple as heat rash or something as painful as shingles.  The term is quite literally a collection of vesicles.

A vesicle will always be filled with air, clear fluid or a milky fluid.  Most vesicles are easily broken open so that the fluid within spills out.  Bacteria within the fluid could infect surrounding areas and create additional pimples.  A solid raised bump is called a papule and, even if it is part of a rash, is not a vesicle.

Vesicles are not necessarily present in every rash.   Some rashes are composed of reddened, flaky skin with no pustules involved.  Not all vesicles are part of a rash, either; for example, a single pimple that appears on the skin does not constitute a rash.  Rashes may begin as a reddened, inflamed patch of skin with vesicles appearing later, or they may begin as a single blister joined soon thereafter by various others. 


 There are certain types of vesicular rashes seen more often than others.  Not all require treatment, although it is always advised to leave the blisters in a rash alone and allow the body it heal itself to avoid spreading of the rash, infection and possible scarring.

  • Chicken pox.  A common childhood illness, chicken pox is highly contagious and can be easily spread through physical contact or from a cough or sneeze from an infected person.  Symptoms of the illness begin with fever, headache and stomach ache, followed by outbreaks of multiple tiny blisters that will break and then crust over to a scab.  Individuals are contagious for two to three days prior to the appearance of the blisters and remain contagious until all of the blisters have crusted over.  Because the rash causes extreme itchiness, it is often spread to other parts of the body by the infected individual himself as well as to others by scratching or touching the blisters.
  • Impetigo.  Impetigo is a contagious bacterial infection that occurs most frequently in children.  This vesicular rash often happens as the result of an unassociated scratch or cut that becomes infected with either the staphylococcus aureus or the staphylococcus pyogenes bacteria.  Practicing good hygiene by keeping open wounds clean and sterile as possible can help to prevent this condition.
  • Herpes zoster.  More commonly known as shingles, this condition is the result of a dormant virus varicella-zoster, which is the cause for chicken pox in children.  As television commercials for certain medications say, if you had chicken pox as a child, this virus is already within you.  It does not become active in all individuals, however.  When it does emerge, the first symptom is a painful, stinging burn, later developing into painful blisters.
  • Herpes simplex.  Fever blisters and cold sores are the types of vesicular rash presented by Herpes simplex, a common viral infection known as type 1 (HSV-1).  Genital herpes is also caused by a variety of this virus, herpes simplex type 2 (HSV-2).  These rashes are also very contagious to others. 
  • Contact dermatitis.  Poison ivy, poison sumac and poison oak are all examples of vesicular rash types of dermatitis.  This inflammation happens when a substance comes in contact with the skin and causes an allergic reaction or irritation.  Other examples could be reactions to certain ingredients in soaps, perfumes or even jewelry.  Contrary to the belief of many people, these types of rashes are not contagious.  It is possible, however, to spread poison ivy, sumac or oak through contact of the urushiol, which is the oily substance produced by the plants and the cause of the dermatitis.  Clusters of tiny blisters appear and create an itching sensation after coming in contact with the plant.  

There are a variety of other types of illnesses, disorders and diseases that may carry the symptom of vesicular rash that are too numerous to name in one list.  The important thing to remember with most of the blisters that are filled with either clear or milky fluid is that this fluid very likely will contain the bacteria or virus that started the outbreak, and will therefore be able to spread the rash of blisters.  It is always best to keep the hands away from these vesicles; resist the temptation to scratch or even rub the affected areas.  There are a number of remedies that can help to relieve the itchiness; oatmeal baths, baking soda paste applications and many commercial creams and lotions designed to alleviate that uncomfortable itch.  It is always recommended, however, to check with your doctor before treating any type of rash to determine its cause.

Despite the ominous name, it is good to know that a vesicular rash is merely a symptom.  The diagnosis of the rash will then require further investigation as to what may have caused the blisters, as the bacteria or virus will still be present within the body and can be treated.