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What is Urticaria?

Brendan McGuigan
Brendan McGuigan

Urticaria is a skin condition more commonly known as hives. It is a rash of varying intensity, with distinctive itchy bumps that can be bright red, and are raised. Most people who suffer urticaria are experiencing it in reaction to an allergen of some sort, but there can be many non-allergen causes as well. There are many different causes, and a large portion of hives have an unknown, or idiopathic, cause. Generally hives are not dangerous, although they can be indicative of a different condition that may be harmful in the long run.

Another name for urticaria is nettle-rash, and many people describe moderate cases as looking like the reaction to being stung by stinging nettle. In severe cases, however, large raised and reddened wheals can cover the body, and the itching can become unbearable. The redness of urticaria is caused by the capillaries leaking out in the dermis layer, and it lasts until the fluid is reabsorbed and leakage stops.

Hives may occur as a result of a food allergy.
Hives may occur as a result of a food allergy.

Allergic urticaria can be caused by any number of allergens, either topical or internal. Many people have allergic reactions to foods and medicines, and if they ingest them they break out into hives of varying degrees of severity. In some cases their allergy may be so severe that even brushing up against the allergen can cause an intense case of hives. An intense allergic reaction takes place, with massive amounts of histamine being released in the area, which provokes and itching response. As a result, taking an antihistamine can help reduce the itching and ultimately can make the rash go away.

Hives may occur as a result of an allergy to certain medications.
Hives may occur as a result of an allergy to certain medications.

Generally an outbreak will not last long, with an average rash lasting only one or two hours. Some cases may last only a few seconds before fading. Often, however, the rash is recurring, so that within minutes or hours of fading a new rash will spring up. In severe cases the rash may last for an extended period of time, although it is very uncommon for hives provoked by an allergy to last more than four to six weeks. If a rash does persist, it is likely non-allergic and may be indicative of an underlying problem.

Anti-itch cream can be applied to alleviate the symptoms of hives.
Anti-itch cream can be applied to alleviate the symptoms of hives.

Hives are often the most frustrating aspect of an allergic reaction for a person. For many people, the unsightly blemish of a mass of reddened, puffy skin is worse than any accompanying pain or malaise that comes with an allergy. The itching in some cases can be virtually unbearable, as well, and there is little one can do about it. Although antihistamines can help in less severe cases, more intense hives can be extremely difficult to manage.

Hives are generally not dangerous, although they can indicate a more harmful condition later on and should still be treated.
Hives are generally not dangerous, although they can indicate a more harmful condition later on and should still be treated.

As a result, the best way to handle hives is to not develop them in the first place, although in the case of viral or idiopathic urticaria, this may not be possible. For those with severe allergies, avoiding allergens is the best way to handle hives. Taking extreme care when around foods that provoke an allergic response, and making sure to watch out for medication that causes hives, is a necessary step to avoid the itching and swelling of this unfortunate ailment.

Discussion Comments

anon145870

I really need help. Sometimes i take a bath and when i get out, both my legs from my knees to toes turn blood red. they are hot and itch like crazy as if they are really dry. I've even made them bleed a time or two.

Plus, the last two toes on my left foot tingle all the time. I pour cold water over them and that seems to help a little but the tingle is always there. can you please tell me what you think it might be?

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    • Hives may occur as a result of a food allergy.
      By: Boyarkina Marina
      Hives may occur as a result of a food allergy.
    • Hives may occur as a result of an allergy to certain medications.
      By: avarand
      Hives may occur as a result of an allergy to certain medications.
    • Anti-itch cream can be applied to alleviate the symptoms of hives.
      By: picsfive
      Anti-itch cream can be applied to alleviate the symptoms of hives.
    • Hives are generally not dangerous, although they can indicate a more harmful condition later on and should still be treated.
      By: Rob Byron
      Hives are generally not dangerous, although they can indicate a more harmful condition later on and should still be treated.
    • Scratching hives may make them itch more.
      By: Piotr Marcinski
      Scratching hives may make them itch more.
    • Urticaria that is accompanied by other symptoms such as a swollen tongue or throat should be addressed by a doctor immediately.
      By: jinga80
      Urticaria that is accompanied by other symptoms such as a swollen tongue or throat should be addressed by a doctor immediately.
    • Severe seasonal allergies and hay fever may cause urticaria.
      By: FedeCandoniPhoto
      Severe seasonal allergies and hay fever may cause urticaria.