Whether you call it eczema or dermatitis, you’ll know if you have it from the red, swollen, itchy skin that characterizes this common dermatological problem.

“There are many types of eczema. Some cases are due to allergic reactions to specific agents, such as the resin from poison ivy plants. However, many cases have no identifiable allergen, such as atopic eczema,” explains Dr. Lawrence Samuels, St. Luke’s Hospital chief of dermatology. Eczema is irritating, but it is not contagious and should not be confused with psoriasis, which is characterized by thicker red plaques that typically appear on the elbows and knees but generally do not itch.

Although it may seem idiosyncratic, atopic eczema tends to run in families, says Dr. Joseph Muccini, a dermatologist with Mid- America Skin Health and Vitality Center. “It’s associated with families where different members may or may not have something from the following menu: asthma, allergies, hay fever or keratosis pilaris, which are tiny bumps around hair follicles on the arms and legs.” He reminds patients that eczema is a reaction to something, not a disease in itself. Babies and children most commonly develop atopic dermatitis, often on the face, inside the elbows, behind the knees, and on hands and feet. Scratching the rash can exacerbate the symptoms and lead to increased redness, swelling and ongoing irritation.

Fortunately, eczema isn’t hard to treat. “All types of eczema tend to respond to topical cortisone cream and skin moisturizers,” Samuels says. “Over-the-counter hydrocortisone cream (1 percent) applied two to three times daily is recommended. In addition, one can take OTC Benadryl to control the itching.”

Muccini adds that looking for the cause of the eczema is important, and he advises that patients adopt a hypoallergenic regimen to help determine what could be triggering a reaction. The regimen includes removing all products that contain fragrances or irritants, using mild soaps and taking lukewarm showers. “I have them use hypoallergenic laundry detergent, stop using additives of every kind whatsoever and start using only premier moisturizers that are hypoallergenic,” he says.

Common irritants include wool or synthetic fibers, harsh or fragranced soaps and cleansers, perfumes and makeup, industrial solutions (such as chlorine, mineral oil or solvents), dust or sand, and cigarette smoke. Dust mites, seasonal pollens and molds, and pet dander also can be associated with atopic eczema. Dry air, exposure to hot water and stress may cause the problem to flare up.

In moderate to severe cases, over-the-counter medications won’t be enough, Samuels notes. “There are several prescription medications, both topical and oral, which are effective. No treatment should ever make the condition worse. Eczema is not contagious, but one tends to develop new spots when treatment is not effective.”

There currently is no evidence that supports the use of dietary supplements to prevent eczema, and some herbal medicines can actually worsen the problem, although some research suggests that drinking oolong tea may be helpful as long as the patient also adheres to a standard medication regimen. The most convincing studies indicate that using moisturizers and medications recommended by your dermatologist, along with behavior modification to help reduce scratching and control stress, can dramatically improve eczema and help keep the problem at bay.