Phoenix Allergist Skin Conditions

Many patients at AAAI suffer from hives or urticaria. Hives are itchy welts that appear on the surface of the skin. They are caused when special cells in your immune system, called mast cells, release histamine. Sometimes mast cells are affected in deeper layers of skin and this causes swelling (angioedema), most commonly in the lips, eyes, hands and feet. Hives typically come and go and move around throughout different areas of the body and of course are very, very itchy.


Acute Vs. Chronic Hives: 

When hives have been occurring for less than 6 weeks, they are called “acute” hives. Acute hives that happen randomly are most commonly caused by a viral or bacterial infection.  Patients that have food or drug allergies may get hives immediately after accidentally ingesting their allergen, which is a sign of an allergic reaction. Others that are allergic to different airborne allergens can get hives when exposed to those allergens as well (such as hives when petting a dog, or from sitting in the grass).


Chronic hives are when hives have been occurring pretty consistently for more than 6 weeks. Chronic hives are often caused by over-stimulation of the immune system which results in mast cells releasing histamine. This condition is often called, “chronic idiopathic urticaria.” The term “idiopathic” means it occurs randomly with no known cause. Chronic, random hives are not caused by a food, a drug or the environment. Often if a patient has suspicion that a food or drug was involved, working with your allergist we can perform a complete history and examination and blood or skin tests if needed to help determine the underlying cause. However, with chronic hives, often no cause is identified.



The good thing is that chronic hives are not dangerous and do not affect one’s long term health. There are multiple safe medications patients can take to control hives and itching while we are waiting for the condition to resolve.  There medications include both second generation antihistamines (such as Claritin, Zyrtec or Allegra) and sometimes first generation antihistamines (such as Benadryl and Hydroxyzine). We will often use antacids such as Zantac and Pepcid, which are acid reflux medications but can also help hives. Singulair can sometimes be used and if hives are severe we can use oral steroids to improve the condition.   If hives or itch are severe and uncontrolled with medications, we can use a biologic (an injected drug that works with your immune system) to improve the hives called Xolair. Allergy medications prescribed for hives need to be taken every day, sometimes twice daily, to help control the condition.  Your allergist or PA will help you determine what the best treatment course is for you!