HivesWhat is “hives”?Hives is an inflammatory condition of the skin, caused by the release of Histamine and other substances that produce changes in the outer layer of the skin.The release of histamine could be caused by allergy or other causes.The medical name for hives is urticaria.Hives may be precipitated by stress. What are the symptoms and signs of hives?- Redness: A red rash appears on the skin caused by blood permeating the skin .
- Wheals: They are areas of raised skin ,usually surrounded by pale color .
- Itching: The red wheals are VERY itchy , and the itching is the main complaint from hives .
What are the types of hives and what causes them?- Allergic urticaria: is an allergic reaction to allergens that usually come into contact with the skin.
However allergens in food could also precipitate hives.
The allergens react with cells in the body that release a massive amount of Histamine.
- Psychological hives: is a type precipitated by anxiety.
It is also caused by a release of Histamine, but in a different way than allergic hives.
- Drug induced urticaria is the most dangerous type because it is associated with failure of the heart and lungs . Some drugs notorious for similar incidents include sulpha drugs (antibiotics and oral hypoglycaemics etc), aspirin, penicillin etc there might or might not be an allergy to the drug involved.
How is hives treated?Since the mechanism of the disease is based on Histamine, obviously Anti-histamines are the mainstay of treatment. Steroids and itching drugs are given too. - Anti-histamines are drugs that antagonize the effect of histamine, they usually cause drowsiness (Promethazine, Prochlorperazine etc), and care should be taken when using them with other drugs that affect wakefulness or with alcohol.
Some anti-histamine do not cause this side effect like Loratadine.
- Steroids can be given orally or as a topical application depending on the severity of the urticaria.
- Anti-pruritic drugs decrease itching and they could be given as tablets or topical applications.
- In life-threatening hives (like in drug-induced urticaria), Adrenaline is required to support the heart function. People who are prone to severe urticaria should always have an adrenaline shot within reach.
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