Urticaria (commonly called welts or hives) are itchy, raised, red or white swollen areas of the skin which may occur on any part of the body. Hives vary in size from pinpoint to as large as a pancake and rarely cover an entire portion of the body. Hives may last from minutes to hours and may recur daily or intermittently. Hives occur when histamine and other irritating (inflammatory) chemicals are released from white blood cells (mast cells) in the skin. These white blood cells are the same ones involved in allergic reactions in the nose and eyes (hayfever) and lungs (asthma) and part of the immune system that ordinarily respond to parasites.
Acute hives are often caused by allergic reactions to foods, medications, insect stings, or latex. Allergic hives start within minutes of exposure and tend to recur with future exposures. Allergic hives may be accompanied by other systemic allergic symptoms like wheezing, swelling in the throat or low blood pressure (anaphylaxis). Hives may also occur with physical stimuli such as cold, heat or pressure, during emotional stress or with viral illnesses such as mononucleosis, viral hepatitis or even the common cold. Rarely hives are caused by a medical problem such as thyroid inflammation or systemic autoimmunity.
“Chronic Urticaria” refers to hives recurring for more than 6 weeks. A cause for chronic urticaria is found in less than 5% of cases. Allergic reactions are not known to cause chronic urticaria and allergy tests are usually not helpful. Recent research has shown that chronic urticaria is usually due to an auto immune reaction to one’s own mast cells in the skin. The cause of this auto immune response is unknown and is not felt to be related to allergy. Chronic urticaria may be referred to as idiopathic or spontaneous.
Angioedema (giant swelling) is large, sometimes distorting, swelling affecting the eyelids, lips, tongue or other parts of the body. Very rarely angioedema affects the throat, but, when it does, it may be life threatening. Giant swelling may occur with or without hives. A very small percentage of these cases have an inherited or acquired deficiency of a blood protein that normally limits swelling (Hereditary Angioedema).
When mast cells are reactive, scratching the skin can result in further release of histamine, making the problem worse. Scratching induced hives (dermographism or skin writing) are common.
When the precise cause of hives/giant swelling is identified, recurrence can be prevented by avoiding the stimulus. When no cause is determined or avoidance is not effective or feasible, control of hives/giant swelling can often be accomplished with the use of medications, even in chronic cases.
Some stimuli may non-specifically worsen hives and swelling.
- Aspirin and aspirin-like medications (Advil, ibuprofen, Motrin, Aleve, etc.) may aggravate chronic hives/giant swelling in more than 50% of cases. Aspirin may be found in many cold and headache preparations (Alka Seltzer, Excedrin, etc.) When hives are active, plain acetaminophen (Tylenol etc.) should be used as a substitute for aspirin.
- Rarely, excessive ingestion of foods containing citric acid (oranges, lemons, grapefruit, tomatoes), spicy foods and vitamin C tablets may cause itching and worsening of hives/giant swelling.
- Alcohol dilates blood vessels and may rarely result in outbreaks of swelling. Avoidance or decrease in intake of alcoholic beverages may be helpful if active swelling is present.
- Codeine and other narcotic medications (such as those found in many cough syrups) may worsen swelling and should be avoided.
- Heat often worsens hives/giant swelling. Hot baths and showers should be avoided during episodes of active If strenuous exercise worsens the hives, this should be avoided or limited.
- Scratching the skin usually causes more itching and swelling. You should avoid anything which causes itching (wool, drying soaps, etc.). Try not to scratch. Instead, use antihistamines as instructed to control the itching.
Generally, hives and swelling can be controlled with combinations of antihistamines. For acute, brief episodes use of a sedating (causes drowsiness) antihistamine like Benadryl can be helpful. However, Benadryl has a short duration of effect and usually can not be taken in the daytime due to drowsiness.
Combinations of 24-hour antihistamines are often used for chronic hives. Some patients require six times the usual dose. Usually a non-drowsy antihistamine like Allegra or Claritin is used in the morning combined with a sedating antihistamine like Zyrtec or Xyzal at night.
A short course of steroid (cortisone) pills may be used to gain control of hives. However, long term use of steroids should be avoided due to potential side effects. Sometimes Zantac (ranitidine), a histamine receptor 2 blocker generally usede, is added to regular antihistamines. However, there are few responders to Zantac. Another medicine sometimes tried for hives is Singulair (montelukast), a leukotriene blocker originally developed for asthma. Unfortunately very few people with hives respond to Singulair.
A new, highly successful treatment for chronic hives was approved in 2014. Xolair, a biologic (monoclonal antibody) was initially developed for allergic asthma in 2003. Studies in 2012-13 showed Xolair helpful for most people with chronic spontaneous (idiopathic) urticaria (hives). Xolair is given in a physician’s office monthly with an observation period to watch for allergic reaction. Fortunately, there are few or no reactions to Xolair and most people improve within 1-2 months. Many people can taper or discontinue their antihistamines and remain itch free. We have had great success with Xolair for hives and have a long history (since 2003) of using it for multiple people with asthma.
If you have chronic hives, contact us for a consultation visit. 512-345-7635.