The goal of treating most cases of ordinary urticaria is to relieve symptoms while the condition goes away by itself. The most commonly used oral treatments are antihistamines, which help oppose the effects of the histamine leaked by mast cells. The main side effect of antihistamines is drowsiness.
Are hives (urticaria) contagious?
Hives are a particular rash that's characterized by itchy, raised, whitish or pinkish welts on the skin. They may occur on one area of the body, such as the stomach or arms, or occur all over the body. Hives rash is triggered by the release of histamine in the skin and is caused by an allergic response. A wide variety of foods, medicines, conditions, and chemicals can cause hives, including foods (such as strawberries and seafood), drugs (such as penicillin and sulfa), and infections (viral, bacterial, and parasites). Frequently, the agent that triggers a hives rash is not detected. Hives are also known as urticaria.
Hives themselves are not contagious unless they contain agents such as viruses that can be transmitted from an infected individual to another. The vast majority of hives are not contagious. Hives occur more frequently in children and in females. In general, hives decrease and disappear within about 24-48 hours if the affected individual is no longer exposed to the allergic agent. If hives last longer than days or weeks, they may be termed chronic urticaria.
How long will it be before someone knows if he or she is going to get hives?
Because hives are response to a large number of different triggering agents, most people don't know if they're going to get hives until they encounter the agent. Sometimes hives occur rapidly within a few minutes to hours after contacting the triggering agent. Other times hives may take longer to develop. About 70% of patients who develop hives initially do not know when they encountered the triggering agent. Often the triggering agent is not identified. Some patients know immediately if they're going to get hives if they inadvertently contact the triggering agent that has caused them to develop hives in the past. Pregnant women are at increased risk of developing hives.
Medically Reviewed by a Doctor on 8/8/2016