Dermatitis is a skin condition that causes red, itchy, flaky or blistered patches of skin. It can be uncomfortable and embarrassing, especially when the rash oozes or cracks.
Your dermatologist can diagnose many types of dermatitis by doing a physical exam and reviewing your medical history. They may also perform a patch test to help identify possible allergens.
The condition causes itchy, red, scaly patches of skin. Symptoms vary depending on the type of dermatitis you have. Rashes often appear on the creases of wrists, elbows and knees or on the face. The rash is usually dry and flaky, but it may be red, swollen and cracked in some cases. It can also cause skin discoloration — patches of the rash might be gray or purple in color, especially on darker skin tones. Inflammation of the rash can lead to blisters, which may open and become infected.
Atopic dermatitis, also known as eczema, is the most common type of dermatitis. It tends to start in childhood and can recur throughout life. It can be triggered by a variety of things, including detergents, perfumes, jewelry made with nickel and certain foods. Itchy rashes can also be caused by cold weather, stress and a problem with your immune system.
To diagnose the type of dermatitis you have, your doctor will do a physical exam and ask about your symptoms and your past health. Your doctor may also do a skin patch test, where they put small amounts of different substances on your skin and monitor the resulting reaction for a few days. They may also recommend a steroid cream, such as hydrocortisone. A cool, moisturizing bath, wearing loose cotton clothing and avoiding rubbing or scratching the affected area can help relieve itching.
Your doctor will perform a physical exam and ask questions to understand the symptoms you’re having. You might be asked about your family history of the condition to uncover clues to its cause. It is also a good idea to bring a list of all your symptoms and when they started.
If the dermatitis is caused by an allergy, your doctor might do a skin patch test. During this test, small amounts of different substances are put on your back and after several days, they’ll check for reactions. Your doctor may also order blood tests to rule out other conditions that might be causing the rash.
Some types of dermatitis are more difficult to diagnose than others. For example, atopic dermatitis has many symptoms and is hard to distinguish from other forms of eczema. Also, urticaria, which looks like itchy red welts and is commonly known as hives, has many symptoms that are similar to those of other skin conditions.
In these cases, a dermatologist will be needed for diagnosis and treatment. Other types of dermatitis include neurodermatitis, which is characterized by itchy rashes on the hands and arms that are often accompanied by blisters; seborrheic dermatitis, which causes flaking, itchy skin on the scalp, face or groin; and irritant contact dermatitis, which usually results from repeated exposure to harsh chemicals — for example, hand soaps and detergents, or scented shampoos and perfumes.
There are many different types of dermatitis. The symptoms vary with each type, but most include redness and itchy skin that can swell or ooze fluid. Some types of dermatitis are inherited (atopic dermatitis, eczema), while others develop due to environmental or occupational exposure to substances that trigger allergic reactions (contact dermatitis). Other types of dermatitis are triggered by the presence of yeast or other bacteria on the skin surface (cradle cap, seborrheic dermatitis).
Your doctor will examine your skin for classic signs of dermatitis such as rashes, redness, scales and itching. They will also ask about your history with dermatitis and other symptoms you may have been experiencing. If your dermatitis is due to allergies, they may recommend patch testing. This involves putting small amounts of different substances on your skin and observing the area over the next few days to see which cause an allergy or dermatitis flare-up.
The most common treatment for dermatitis is to use lotions or creams that keep the skin moist and decrease irritation. Your doctor may also prescribe oral medications that decrease itching and inflammation, including antihistamines, calcineurin inhibitors and phosphodiesterase-4 inhibitors. There are also new biological drugs or biologics that target the functions of your immune system to reduce dermatitis. In some cases, your doctor may recommend a short course of corticosteroid injections to reduce the inflammation associated with certain forms of dermatitis such as contact dermatitis and psoriasis.
The best way to prevent some types of dermatitis is to avoid contact with the substances that trigger them. If the irritant is a plant like poison ivy, oak or sumac, wash the affected skin and all clothing as soon as possible with soap and water (and wear rubber gloves at work when exposed to these plants). The itching that occurs in some types of dermatitis can be reduced by taking an oral antihistamine medication. Scratching the rash can spread the inflammation and cause open sores that may become infected and leave scars.
Some types of dermatitis can be caused by factors that are harder to avoid, such as working with certain metals or solvents in the workplace, having a health condition like asthma or HIV/AIDS, or wearing tight-fitting clothes. These types of dermatitis tend to occur on the hands and forearms. They may also be triggered by emotional stress, seasonal changes or environmental factors.
A rash from dermatitis is not contagious, but it can be very uncomfortable and distracting. To improve your quality of life, talk to your doctor about ways to manage dermatitis symptoms at home. Applying ointments, creams or lotions several times a day can keep the skin hydrated and reduce itching. Moisturizers should not contain perfumes, dyes or alcohol. Bathing with mild soaps can help, but not harsh detergents. Using cool, wet compresses can relieve itching. Keep the itchy areas covered when not at work or sleeping (to reduce scratching). Trim fingernails and wear light gloves at night if you have trouble keeping from scratching the itch.