Hives: Causes and Treatments
Hives: Causes and Treatments
Urticaria, also known as hives, is a common condition of the skin
characterized by a red, itchy rash. There are many different causes. Allergic
reactions occur when a trigger, such as a food or insect bite, causes
a reaction leading to histamine release. Insects that can cause a reaction
leading to hives include hornets and fire ants. Certain foods, such as
eggs and nuts, can cause an allergic reaction, typically within 30 minutes.
Latex, soaps, and detergents also can lead to hives. Certain medications,
including penicillins and sulfa-containing medications, can also
result in allergic reactions.
Treatment of hives largely involves identifying and avoiding reaction
triggers, such as a certain food or type of detergent. Antihistamines
are used to control associated itching, which is a result of histamine
release. Antihistamines are classified as histamine-1 (H1) receptor
blockers and histamine-2 (H2) receptor blockers. Hydroxyzine (Atarax,
Vistaril) and diphenhydramine (Benadryl) are first generation H1 receptor
blockers, and may cause drowsiness. Second generation H1 receptor
blockers are more likely used for persons with hives lasting more than a
few days. Loratadine (Claritin) and cetirizine (Zyrtec) are examples of
second generation H1 receptor blockers. They tend to be less sedating
than the H1 blockers.