HIVES Hives, medically referred to as Urticaria, may be caused by an allergic reaction. However, in some cases, there is no clear cause for the rash. Hives, can result when certain skin cells (calls "mast cells") release histamine or other chemicals into the blood. These substances may cause blood vessels to leak fluid and cause hives to form. Hives may also occur due to internal factors or diseases with no allergies involved. It is the job of the Allergist to try and eliminate the origin of the hives if possible. If the hives last less than six weeks, it is called "acute urticaria". If they last greater than six weeks, it is called "chronic urticaria". Known Triggers to Cause Hives Allergies (e.g., to soap, cosmetics, cleaning agents, or detergents) Emotional stress Physical stimuli, pressure, vibration Food additives or preservatives Food allergies (e.g. to eggs, milk, berries, shellfish, tomatoes, nuts, or chocolate) Infections (e.g., viral illnesses, colds, hepatitis, other bacterial and fungal infections) Insect bites and stings Medications (e.g., antibiotics, non-steroidal anti-inflammatory drugs [NSAIDs], laxatives, vitamins, herbal and diet supplements, sedatives, tranquilizers, diuretics, pain medications, eye drops, ear drops) People with a family history of hives and those who have had a previous allergic reaction are at increased risk for developing hives themselves Signs & Symptoms: Raised area of skin called a wheal. In some instances wheals can join together and form a rash that can cover the entire body. Intense itching. Hive symptoms may worsen with extreme heat, stress, or physical exertion. Hives often occur on the face, hands, and/or feet. Some hives have reddish patches, called flares or "halos," that surround the wheals. The rash may change in shape and size and can disappear and then reappear, sometimes in different places on the body. Hives usually last from 30 minutes to 36 hours, but they may last weeks or months in some cases. In order to properly treat your hives we would need to determine what is causing them. Premier Allergy and Asthma Associates can conduct detailed testing such as patch testing and prick testing to help identify the allergens that might trigger a reaction of hives. Treatment for the hives may be as simple as removing yourself from exposure to the "trigger" or participating in immunotherapy (allergy vaccine) to reduce the reaction caused by that allergen. Reducing emotional and physical stress can also help to prevent hives.