About one in four of us has had it at some time or another: the red, itchy skin rash (called contact dermatitis) that results from being exposed to an allergen or irritant. From adhesives to zippers, just about anything can cause a rash if it comes in contact with the right (or wrong) person’s skin.

Allergens

Allergic reactions are a major source of contact dermatitis. In many cases, a rash will appear right after contact with an allergen, but some reactions may take more time to form. The most common skin allergens include:

• Nickel (especially belt buckles, zippers, and clasps in clothing worn next to the skin)
• Topical medications (especially antibiotics)
• Skin or beauty products (cosmetics, deodorants, perfumes, nail polish, moisturizing soaps, and lotions)
• Chemical proteins in latex gloves and other rubber-based medical supplies
• Plants (poison ivy, poison oak, and poison sumac)

Chemicals and other irritants

If your hands itch whenever you wash the dinner dishes, imagine how your skin would feel after a day of professional housecleaning. Excessive contact with the harsh chemicals in detergents and solvents can cause itching, redness, and discomfort, especially on the hands (where most of the contact occurs). Chronic exposure to these irritants can roughen and thicken your skin.

To reduce your exposure to chemical irritants, wear gloves while you work. If you’re allergic to latex, wash your hands often with a moisturizing soap or use nonlatex gloves. For oily substances such as oven grease, rinse off with a mild alcohol solution.

Beware, however: Itchiness can also be a sign of dry skin from overwashing, which removes the natural protective oils from your hands. To rehydrate, apply a nonirritating moisturizing lotion each time you wash your hands.

Heat

In hot, humid conditions, pores may become blocked or inflamed, causing perspiration to get trapped in the skin. This is called a heat rash (in adults) or a diaper rash (in infants). You can identify a heat rash by its characteristic tiny pimples, which form over the clogged pores.

Keep in mind that hot, humid conditions aren’t limited to the summer months. For instance, people get heat rash from sweating under many layers of winter clothes. To prevent heat rash in hot weather, wear lightweight, loose-fitting clothes. In cold weather, dress in thin layers that you can remove as needed.

Diagnosis and treatment

If you suspect you have contact dermatitis, see your health care provider for diagnosis and treatment. He or she can do a patch test to find your contact dermatitis triggers. In a patch test, a diluted form of a suspect trigger is applied to the skin for a set amount of time (usually two days). If you are sensitive to the substance, a rash will appear in the patch area.

Avoiding your triggers is the best treatment for contact dermatitis. But most people can’t avoid all triggers, all the time. Talk to your health care provider about the best treatment. In minor cases, you can relieve symptoms by applying an over-the-counter hydrocortisone cream to the affected area. If itching is a problem, an over-the-counter antihistamine may do the trick. Cold water soaks or cold compresses can also relieve contact dermatitis symptoms. See your doctor if the rash:

• Lasts more than a week
• Continues to worsen, even after self-treatment
• Is accompanied by fever, chills, swollen glands, or other symptoms of infection

In rare cases, exposure to some allergens can result in a serious, life-threatening reaction called anaphylaxis. Symptoms may include hives, difficulty breathing, nausea, fever, and increased heart rate. If you experience these symptoms, get emergency medical help.

Triggers are different for everyone, depending on individual sensitivities. By learning to recognize your triggers — and to avoid them when possible — you can stop contact dermatitis before it starts.

This entry was posted on Wednesday, July 25th, 2007 at 7:06 am and is filed under Skin Concerns. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.