Hives - Causes, Symptoms, Diagnosis and Treatment

Ian C. Langtree - Writer/Editor for Disabled World (DW)
Published: 2010/10/13
Topic: Skin Conditions - Publications List

Page Content: Synopsis - Introduction - Main

Synopsis: Hives are commonly an allergic reaction to either a medication or food.

Introduction

Main Item

The rash of hives can happen anywhere on a person's body, yet occurs most often on a person's chest, face, back, or abdomen. The rash is comprised of patches that are raised and vary in size from very small to very large. The patches have the potential to merge with each other, creating larger patches referred to as, 'wheals.'

Patches of hives can be wavy or round in shape, with edges that are called, 'serpiginous,' or, 'snake-like.' The edge of the patches are thick and red, although the middle of the patches may be red like the edges are, lighter shades of red, or even pale in color. The patches are very itchy most of the time, and come and go, lasting from an hour to a day or more. When the patches of hives disappear, the affected person's skin returns to its usual condition where the patch once was.

Hive rashes many times come in waves, Patches of hives may appear, fade; then be replaced by new patches of hives that can appear in different places. There are a few people who experience hives lasting greater than several weeks, a condition referred to as, 'chronic uticaria,' something that may be the sign of an underlying illness.

Causes of Hives

When a person experiences an allergic reaction to a substance, their body releases histamine, as well as additional chemicals into their bloodstream. The result is itching, swelling, and other symptoms. Hives are a common form of reaction, particularly in people who experience other forms of allergies. When welts or swelling happen around a person's face, particularly around their eyes or lips, the condition is referred to as, 'angioedema.' Swelling from the condition may also happen around a person's feet, hands, and their throat. A number of substances can initiate hives, to include:

• Pollen
• Molds
• Exercise
• Vibration
• Chemicals
• Insect bites
• Medications
• Animal dander
• Pressure on the skin
• Shellfish, fish, nuts, eggs, milk, and other foods

Additional causes of hives include emotional stress, excessive sweating, extremes in temperature, sun exposure, and infections such as mononucleosis. Illnesses to include leukemia and lupus may also cause hives. In many cases, the cause of the hives a person experiences cannot be found, something referred to as, 'idiopathic uticaria.'

Symptoms

The symptoms of hives include itching, as well as swelling of the surface of the person's skin into either skin-toned or red-colored welts, with clearly defined edges. The welts might become larger and spread, joining together to form larger areas which flatten on the person's skin. The welts may change in shape, fade or disappear, only to reappear within a period of minutes to hours. The welts associated with hives can begin rapidly, the disappear suddenly. When pressed in the center, the welt turns white, something called, 'blanching.'

Diagnosing Hives

A doctor can determine if a person has hives by examining their skin. If a person has a history of allergies, the diagnosis is even more clear. On occasion, a blood or skin test may be ordered to confirm that the person has experienced an allergic reaction, as well as to test for the substance which caused the allergic response.

The majority of people do not require testing to discover the cause of the hives they have; the rash disappears within a fairly short period of time, and the person does not experience an ongoing problem. At times it is pretty easy to figure out the cause of the hives through checking what the person has been exposed to, although it may be hard because the hives may not appear for hours to days after the person was exposed. Skin testing can be useful if the person experiences hives often. Infections and illnesses also need to be considered as a cause of hives, and testing performed as appropriate.

Treatment

Treatment for hives might not be necessary, if the hives are mild enough. The hives may disappear on their own, or quickly. In order to reduce the itching and swelling associated with hives there are some different things a person may do. These things include:

• Avoid taking hot showers or baths
• Take antihistamines such as diphenhydramine
• Avoid excessive heat, spicy foods, aspirin, and alcohol
• Avoid irritating the area where hives are present with clothes that are tight-fitting

If a food source is believed to be the cause of hives that keep returning, elimination of the food might be attempted. All foods that commonly cause reactions in a the person should be eliminated for a period of time to determine if the rash disappears, then potentially introduced once again in small doses to find out if the reaction re-occurs. The effort should be pursued with the assistance of an allergy specialist or dietitian.

If the reaction a person experiences to hives is severe, especially if the swelling involves the person's throat, they might need an emergency shot of epinephrine or steroids. Hives in the back of a person's throat might block their airway and make it hard for them to breathe. If the rash or allergic reaction is severe, a doctor may prescribe an oral corticosteroid. If the person with hives is experiencing difficulties with breathing, it is important to seek medical attention.

Possible Complications

Anaphylaxis is a potential complication of hives. Anaphylaxis is a potentially life-threatening and whole-body allergic reaction that causes a person to have difficulties with breathing. The condition causes swelling in the affected person's throat and may lead to a life-threatening blockage of their airway. In addition to potential breathing difficulties, the substance that causes hives might also cause swelling in a person's intestinal tract, leading to abdominal pain.

Author Credentials: Ian was born and grew up in Australia. Since then, he has traveled and lived in numerous locations and currently resides in Montreal, Canada. Ian is the founder, a writer, and editor in chief for Disabled World. Ian believes in the Social Model of Disability, a belief developed by disabled people in the 1970s. The social model changes the focus away from people's impairments and towards removing barriers that disabled people face daily. To learn more about Ian's background, expertise, and achievements, check out his bio.