Hives (urticaria) in adults are triggered by some of the same factors that trigger hives in children and teenagers. Among these triggers or causes of hives in adults are allergic reactions. Adults may have allergies to such substances as medication, food, preservatives and pet dander. In allergic responses to these triggers (either from ingesting or touching the allergens), these adults develop hives on their skin within any amount of time between a few minutes and a few hours.

Allergic hives typically present as acute hives. As long as one is able to remove the allergen from his or her environment, the hives symptoms ultimately resolve and do not recur. If one should fail to identify the substance, then it is possible to be exposed to it again and again, resulting in hives episodes without relief. This could easily happen with a substance like food coloring or a food preservative. Most people are unaware that they ingest these substances when they eat processed foods. Hence, they are not likely to know which foods contain them or that they are repeatedly exposing themselves to allergens.

Autoimmune disease is another cause of hives in adults. Various autoimmune disorders, including lupus and thyroid disease, are associated with outbreaks of chronic hives. Some studies on the connection between hives and thyroid disease have shown greater prevalence of thyroid autoantibodies among patients with hives. Upon treatment for thyroid disease, these patients’ hives have cleared. The studies, therefore, indicate a definite connection between autoimmune disease and the development of hives, even though the mechanisms behind such a connection remain largely mysterious.

Stress and Infection as Triggers of Hives in Adults

Stress is yet another common trigger of hives in adults. This should not come as a surprise, given the high levels of stress endured by adults at their places of work and in other aspects of life. Younger age groups do experience stress. However, children tend to be shielded from the extremes of stress by the adults in their lives.

When urticaria in adults is associated with stress, it tends to present as a chronic condition. If the stress is not addressed, then the urticaria endures. In addition, chronic stress weakens the immune system, increasing patients’ vulnerability to infection and to psoriasis, an autoimmune disease which manifests as a skin condition.

Various infections, including viral, bacterial, fungal and parasitic infections can also be considered reasons for hives in adults. These infections vary. They may include urinary tract infections, infections of the gastrointestinal tract, ENT infections, upper respiratory tract infections and infections of the dental area. When these infections are successfully treated, the associated hives vanish, indicating that there is a connection between infection and the prevalence of hives.

When the search for the cause of hives, or urticaria begins, keep an open mind. What is the cause of urticaria in one person will not have any effect in another, and the cause for hives in the same person may change in different stages of life. There are a few areas that will likely hold the answer if it is to be found and those are the areas you should focus on when searching for your own cause of hives.

Can stress cause hives?

One cause of hives that is often overlooked is stress. While there are certainly foods that cause hives, stress can be a cause of hives more often than you may think. One easy way to begin your detective work is to start keeping a journal on a small pad you can carry with you. Record what you eat, record events that happen during the day. If the hives cause is food it should become apparent fairly soon. They will appear suddenly and quickly and you’ll be able to look at what you ate. A pattern will be apparent if the cause of hives is food.

Stress is a different matter. If you are going through a major life event like a job loss, or divorce, the recurrence of hives will not be triggered by any certain food and will come and go seemingly at random. But you may notice that an argument with a co-worker or spouse triggers a hives event. The cause of urticaria could be a certain stressful time of the day for you, such as before a daily meeting, or your dreaded commute home. The hives themselves will not appear any different regardless of cause, so your event journal may bring something you didn’t think of before. Stress has many physical manifestations and there is no reason to think that it could be the cause of hives in adults just as it affects other organs like the heart or lungs. Since the skin is the largest of all the organs, the effect of stress on the skin could be the cause of hives, rashes, acne, or other skin problems. Stress certainly makes us sweat, and sweat is one known cause for hives. A detailed journal will help you uncover your own stressors. Stress should really not be overlooked as the cause of urticaria, it is the case more often than most people think, especially in a single event or outbreak.

Diseases that cause hives

Autoimmune diseases like lupus are a known cause of hives and if you have one of these diseases, chronic hives may be one of the symptoms. Any autoimmune disease you may have would be a probable cause, since hives is an immune system response.

Thyroid disease is by far the most common disease that can be a cause of hives. But there are other illnesses that cause hives, some of which are listed below.

• Lymphoma
• Carcinomas
• Amyloidosis
• Mastocytosis
• Polycythemia Vera

And Juvenile Rheumatoid Arthritis is often a cause of hives in children.

Allergies that cause hives

When most people think about what can cause hives, allergies come to mind. But the truth is that chronic hives are hardly ever caused by allergies. Pet allergies are the most common allergic cause of hives, but only in acute cases. Some of the more common allergies to be the cause of urticaria are:

• Medications (especially codeine and NSAID drugs)
• Fungus spores or pollens can be a cause of urticaria for those who otherwise suffer from seasonal allergies
• Latex
• Insect Bites or stings
• Dairy products
• Nuts (especially peanuts)
• Fish (shellfish are a notorious cause of urticaria)

Cause of urticaria can be hereditary

Finally, don’t forget to ask family members if they have a history of hives. This will not help you treat your own case but may hel you understand your own cause of hives and come to terms with the fact that you may never find the urticaria cause.