Hives (or urticaria) will affect 1 out of 5 people during their lifetime. They are itchy, red or skin colored bumps with redness around them that come and go. Histamine is the substance that actually causes the hives. This means that if you have hives, they are the result of histamine being released from your mast cells.
If we track down what caused the histamine release then we know the cause of the hives! Some examples are:
- An allergic reaction occurs when an allergy antibody (IgE) meets the foreign substance it recognizes (in essence, this is the substance you are allergic to). This is a very common cause of hives and it happens very soon after exposure. The reaction happens each time you have exposure and is often accompanied by other symptoms like runny nose, difficulty breathing, swelling of the throat, etc. An Allergist will review the history of the event with you because that gives the main clues to what you might be allergic to. Skin or blood allergy testing is often done to confirm the cause of the hives.
- Direct release of histamine from the mast cell can be caused by a number of things. Insects, like mosquitos, spit a blood thinner into your skin with their sting and this releases the histamine that causes hives. Medications such as morphine, codeine, or vancomycin directly release histamine and make certain people feel very itchy. Certain foods like strawberries can do this, too.
- Other parts of the immune system release histamine, too. Many infections and some reactions to medications can set off the Compliment or Kallikrein Systems. We see three to ten day hive outbreaks in children quite commonly because of this. It can be miserable! In this case, to stop the hives you must get over the infection or stop taking the drug causing the hives.
- Physical Urticarias are uncommon but no less itchy! For those who suffer from physical urticaria, getting too cold, too hot, the wrong frequency of vibration or light, or even getting wet will set off the itch.
- In many patients with chronic, spontaneous hives that have gone on well beyond six weeks, an autoimmune mechanism is responsible. Their immune system incorrectly recognizes part of the mast cell as being foreign. This reaction causes the mast cell to then release histamine and makes one itchy.
Whatever is causing your hives, we know that the itch is terrible! Getting relief quickly is important.
If you or a loved one suffer from hives, you need to start paying careful attention to the “Why” (why you are having the reaction, or more specifically, what is causing the reaction) and then “Avoid or Cure”. Your primary care provider can be very helpful in getting this done right way. Then, getting appropriate evaluation and treatment is very important. Not all hives need expensive labs and testing. The history and physical examination are the most important part of finding the “Why”.
Allergists and Dermatologists tend to see the more puzzling cases. An Allergist is most often involved with cases requiring allergy testing for confirmation of diagnosis. If you are needing additional help diagnosing your hives, Dakota Allergy & Asthma is here to help.Schedule your appointment HERE.
