Causes of Hives
- Allergies to foods, especially peanuts, eggs, nuts, and shellfish
- Insect stings or bites
- Medications, such as aspirin and antibiotics (sulfa, penicillin)
- Heat, and/or cold
- Infections, including: the common cold, urinary tract infection, strep throat, infectious mononucleosis, hepatitis, and other viral infections
- Allergens which are present as particles in the air or that touch your skin
In most cases, the hives resolve when the cause is eliminated.
The cause of chronic urticaria often cannot be identified. It is thought to be related to a person's own immune system about 50% of the time. These cases are called idiopathic urticaria. Some types of chronic urticaria are associated with:
- Changes in temperature
- Emotional stress
- Alcoholic drinks
- Menstrual periods
- Pressure hives - people sitting on their buttocks all day, or wearing a belt too tightly.
- Sun exposure
Signs And Symptoms
Hives can appear on any part of the body. They are red or flesh covered. Hives are often round or disc-shaped, and often change shape, move around, disappear and reappear over short periods of time. When pressing the center of a red hive, it turns white, a process called blanching.
Write down your symptoms and signs, when they occurred and how long they lasted. The diary may help you identify triggers, which should then be avoided. For people with pressure urticaria, wearing loose clothing made of smooth fabrics may help avoid irritation.
- Antihistamines are the standard treatment for hives. They reduce itching and swelling. Low-sedating or non-sedating antihistamines are preferred because they have minimal side effects. A physician may use a combination of 2 or 3 antihistamines. Lortadine (Claritin), cetirizine (Zyrtec) or diphenhydramine (Benedryl, others) are over the counter, and may relieve itching.
- Corticosteroids may be used for severe hives, temporarily. An oral drug, such as prednisone, can reduce swelling, redness and itching
- Autoimmune drugs may be used if antihistamines and corticosteroids are ineffective. They may help suppress an overactive immune system.
Cool, wet compresses may soothe the skin and prevent scratching. A comfortably cool bath may relieve itching. Add baking soda, uncooked oatmeal or colloidal oatmeal (finely ground, for the bathtub). Hives – Causes, Symptoms, Treatments And Prevention
Your Questions About Hives Answered
I had hives once last summer. Will I get it this summer? If you know what caused the hives before, you can avoid whatever caused it. You may get hives in reaction to something else, however.
Is there a vaccine for hives? No. There is a countless number of things which can cause hives. It isn't possible to vaccinate against everything.
Are hives contagious? No, because it is not usually caused by an infection. If your hives are in response to an infection, you may pass on the infection, but you don't pass on the hives.
The spot where I got my flu shot got red, itchy and tender. Was that a hive? No, it was just a localized irritation of the site where you got your flu shot.
Is it possible to get hives from an allergic reaction to a person? It's extremely rare, but it has happened. It may not be the person, though, but fabric, soap, lotions or some substance the other person uses and lingers on their clothing or skin.
It seems like I get hives all the time. What should I do? First, see your family doctor. He or she may investigate the causes or refer you to an allergist, a doctor who specializes in treatment of allergies.
Will I "grow out of" having hives? Anyone can get hives. If you tend to react to situations or substances by getting hives, you may get them in the future, no matter your age.
Do hives run in families? Yes, there does seem to be a genetic tendency to get hives.
I got bad hives and my doctor told me to carry a syringe for emergencies. What's she talking about? Severe hives may be associated with sudden, severe swelling in the mouth and throat, cutting off getting enough oxygen when you try to breathe. Death can occur before medical help arrives. The specially prepared injection contains epinephrine, to reduce the swelling in an emergency. The person carries the device to self-inject when extreme symptoms may put his/her life at risk.
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