Submitted by Doug Leone, MD and Adrienne Schupbach, MD, Dermatology and Mohs Surgery Institute
Have you ever experienced a red, itchy rash and wondered what it was and where it came from? Maybe the rash was blotchy, bumpy, or swollen. Maybe it seemed to disappear and then reappear. Maybe it spread so that it morphed into a mass of rashes. You may be suffering from hives.
Hives are a very common type of rash. They itch and are usually swollen red and white welts that can appear on any part of the body. They can be large or small, last for a few hours or a few weeks, and often change shape. They are most often caused by an allergic reaction to a drug or food. Other causes or triggers include reactions to infection, stress, and environmental factors like heat and sun exposure. Allergic reactions cause your body to release chemicals that can make your skin swell up in hives. People who have other allergies are more likely to get hives. The most common treatment is an antihistamine to relieve the itching. Other types of medicine may be needed for a case of hives that is more serious or becomes chronic.
There are several other skin rashes that are often mistaken for hives and it is important to determine what type of rash you have, what caused it, and how to treat it.
Heat rash often looks similar to hives, but the bumps are more like pimples. Heat rash most often occurs in infants and babies where hives occurs in people of all ages. As the name implies, heat rash is caused by hot, humid weather. It will usually clear up fairly quickly by controlling the temperature and allowing the skin to air out. Be careful in applying lotions or creams as these can irritate the skin even more.
Contact dermatitis is a condition in which the skin becomes red, sore, or inflamed after direct contact with a substance. Like hives, contact dermatitis can be tricky to diagnose because it doesn’t always look the same, the symptoms vary, it can appear right away or several days after initial exposure, and it can be long-lasting or very brief. Contact dermatitis appears only on the area of skin that is exposed to the irritant, where hives can spread to any part of the body.
Eczema can be found on any part of the body and often looks very similar to hives. However, eczema is not usually caused by exposure to a substance, but is related to an over-active immune system that causes the red, dry, irritated patches of skin. The treatment for eczema is completely different than that for hives, so it’s especially important to have the correct diagnosis.
Pityriasis rosea is a common skin disease that begins with a red rash or patch that resembles hives. After a few weeks, smaller rashes appear. The rashes usually last six to eight weeks and sometimes longer. No one knows what causes pityriasis rosea, but it is generally not serious and goes away on its own. Even though there is not much in the way of treatment, it’s important to see a dermatologist to be sure of the correct diagnosis and to get relief for the itching.
Most rashes are not harmful and will often resolve on their own within a few days. It is helpful to avoid heat, stay in air conditioning, take cool baths or showers, wear lightweight, loose-fitting clothing, and avoid scratching. Any rash that persists for more than 48 hours or seems to be getting worse should be evaluated by a dermatologist to get a proper diagnosis, make sure that it isn’t a symptom of a more serious underlying issue, and get started on the correct treatment. A dermatologist can usually distinguish the fine differences in rashes just by examining the skin, although sometimes, further testing might be necessary.
For more information, you may contact the Dermatology and Mohs Surgery Institute at 309-451-DERM (3376) or
www.dermatologistbloomington.com. Dr. Leone and Dr. Schupbach, both residents of Bloomington, are board-certified dermatologists, specializing in medical and cosmetic dermatology, including the treatment of skin cancer, moles, acne, rashes, warts, and all skin disorders. Dr. Leone is one of the few Mohs-trained surgeons in the area. Their practice is located at 3024 E. Empire St. 2nd floor, in the Advocate BroMenn outpatient center.