William L Weston, MD
William Howe, MD
Robert P Dellavalle, MD, PhD, MSPH
Rosamaria Corona, DSc, MD
DERMATITIS OVERVIEW — Dermatitis is defined as an inflammation of the skin. Contact dermatitis refers to dermatitis that is caused by contact between the skin and a substance. The substance can be an allergen (a substance that provokes an allergic reaction) or an irritant (a substance that damages the skin). Irritants are responsible for about 80 percent of cases of contact dermatitis.
In most cases, self-care measures and drug therapy can control the symptoms and prevent complications of contact dermatitis.
Topic reviews about other skin conditions are also available. (See “Patient information: Atopic dermatitis (eczema)” and “Patient information: Psoriasis” and “Patient information: Poison ivy”.)
IRRITANT CONTACT DERMATITIS — Irritant contact dermatitis occurs when the skin comes in direct contact with a substance that physically, mechanically, or chemically irritates the skin, causing the normal skin barrier to be disrupted.
Cause — The most common causes of irritant dermatitis are products used on a daily basis, including soap, cleansers, and rubbing alcohol. People with other skin conditions, dry skin, and light-colored or “fair” skin are at greatest risk, although anyone can develop irritant dermatitis.
Symptoms — Mild irritants cause redness, dryness, fissures (small cracks), and itching. Strong irritants may cause swelling, oozing, tenderness, or blisters (picture 1). The hands are commonly affected, often between the fingers. Irritant dermatitis can also affect the face, especially the thin skin of the eyelids.
Diagnosis — The diagnosis of irritant contact dermatitis is usually based upon a person’s history and physical examination. In some cases, a patch test (applying a small amount of a substance to the skin) may be recommended to determine if the dermatitis is allergic or irritant-type. Patch testing should be done by a dermatologist or allergist who is trained in this procedure.
Treatment — The goal of treatment of irritant contact dermatitis is to restore the normal skin barrier and protect the skin from future injury. Reducing exposure to known irritants is essential. In some cases, simply reducing the use of soap and using an emollient cream or ointment completely alleviates symptoms. Wearing gloves when working with irritants may help as well.
In more severe cases, topical corticosteroids (steroids) may be recommended. Steroid creams and ointments are available in a variety of strengths (potencies); the least potent are available in the United States without a prescription (eg, hydrocortisone 1 percent cream). More potent formulations require a prescription.
Steroid treatments for contact dermatitis are most effective when applied and covered with a barrier, such as plastic wrap, a dressing (eg, Telfa), cotton gloves, or petroleum jelly. Oral steroids (eg, prednisone) may be used briefly to treat severe dermatitis, but are not recommended for long-term treatment of irritant contact dermatitis.
ALLERGIC CONTACT DERMATITIS — Allergic contact dermatitis occurs when the skin comes in direct contact with an allergen. This activates the body’s immune system, which triggers inflammation. Allergic contact dermatitis can occur after being exposed to a new product or after using a product for months or years.
Common allergens — Poison ivy, poison oak, and poison sumac contain an oil called urushiol, which is the most common cause of allergic contact dermatitis. Ginkgo fruit and the skin of mangos also contain urushiol and can cause allergic contact dermatitis. (See “Patient information: Poison ivy”.)
Other common allergens include nickel in jewelry (picture 2), perfumes and cosmetics, components of rubber, nail polish, and chemicals in shoes (both leather and synthetic) (picture 3).
Allergic contact dermatitis can also be triggered by certain medications, including hydrocortisone cream, antibiotic creams (eg, Neosporin®, Bacitracin®), benzocaine, and thimerosal. Laundry detergents are an uncommon cause of allergic contact dermatitis.
Symptoms — Symptoms include intense itching and a red raised rash. The rash is usually limited to areas that were in direct contact with the allergen, but a rash can appear in other areas of the body, if the allergen was transferred to those areas on a person’s hands (picture 4). Washing the allergen away with soap and water can usually prevent this spread.
The rash typically appears within 12 to 48 hours of exposure to the allergen, although in some cases it may not appear for up to two weeks. Less commonly, the rash persists for months or years, which makes it difficult to identify the cause of the reaction.
Diagnosis — The diagnosis of allergic contact dermatitis is based upon a person’s history and physical examination. If symptoms improve after the allergen is eliminated, this supports the diagnosis. Patch testing may be recommended in some cases and is usually performed by a dermatologist or allergist.
Treatment — Allergic contact dermatitis usually resolves within two to four weeks after the allergen is eliminated, although it can take more time in some cases. Several measures can minimize symptoms during this time and help to control symptoms in people who have chronic allergic contact dermatitis.
- Whenever possible, identify and stop all exposure to the allergen.
- Oatmeal baths or soothing lotions such as calamine lotion can provide relief in mild cases.
- Topical antihistamines (eg, Benadryl® cream) may be effective in some people.
- Topical corticosteroids (steroids) may be recommended for people with mild to moderate symptoms. Steroid creams and ointments are available in a variety of strengths (potencies); the least potent are available in the United States without a prescription (eg, hydrocortisone 1 percent cream). More potent formulations require a prescription.
- For people with more bothersome symptoms, wet or damp dressings are recommended, especially when the affected area is oozing fluid and crusting. Such dressings are soothing and relieve itching, reduce redness, gently remove crusts, and prevent additional injury from scratching.
A damp cotton garment (the garment is soaked with water and then wrung out) is worn over the affected area and covered with a dry garment. As an example, for an adult with allergic contact dermatitis of the legs, wet long underwear can be covered with larger dry long underwear. Adults may prefer to apply wet dressings at night. When used during the day, wet dressings should be changed every eight hours. Infants and toddlers with extensive skin involvement can wear wet pajamas covered by a dry pair of pajamas or a sleep sack.
- In people with severe dermatitis, a short course of oral steroids (eg, prednisone) may be recommended to get symptoms under control.
LATEX DERMATITIS — Latex is a fluid produced by rubber trees that is processed into a variety of products, including gloves, balloons, and condoms. In some individuals, exposure to these products and others (such as rubber bands, erasers, feeding nipples, pacifiers) can cause a contact dermatitis that is either an irritant or allergic reaction. Less commonly, a person can develop a potentially life-threatening allergic reaction to latex.
Irritant dermatitis — Irritant dermatitis usually occurs on the hands of people who wear latex or other rubber gloves; the latex acts as an irritant and the gloves trap moisture against the skin. The skin dries out when the gloves are removed, leading to the dermatitis.
The symptoms of irritant rubber or latex dermatitis include redness and itching on the skin. There may also be dryness and cracking. Symptoms usually occur within 12 to 36 hours of touching a latex product. Treatment involves avoiding use of any latex-containing products.
Latex allergy — Latex can trigger allergic contact dermatitis. The skin reaction caused by a latex allergy does not differ significantly from that of irritant latex dermatitis.
Other manifestations of latex allergy include urticaria (hives) immediately after contact with latex at the site of contact and a severe allergic reaction, which causes swelling, sneezing, and wheezing. Rarely, anaphylaxis can occur, which causes life-threatening difficulty with breathing (see “Latex allergy: Epidemiology, clinical manifestations, and diagnosis”).
Diagnosis — In most cases, the diagnosis of latex allergy is based upon a person’s history of exposure.
People with a severe latex allergy may immediately develop hives, nasal symptoms, swelling, or wheezing after latex exposure. These individuals may need to see a dermatologist or allergist for specialized skin patch tests and blood testing to verify the latex allergy.
Treatment — The primary treatment for latex allergy is to avoid all latex-containing products. Non-latex examination gloves are widely available, and use of glove liners may also be an effective approach. (See “Latex allergy: Management”.)
Natural membrane (sometimes called sheep skin) condoms may be used in place of latex condoms, and are effective for preventing pregnancy. However, natural membrane condoms do not protect against sexually transmitted diseases such as HIV, gonorrhea, and chlamydia. (See “Patient information: Barrier methods of birth control”.)
People with a serious latex allergy should wear a bracelet, necklace, or similar alert tag at all times. If a reaction occurs and the person is too ill to explain their condition, this will help responders provide the proper care as quickly as possible. This measure is especially important in children. The alert tag should include a list of known allergies, as well as the name and phone number of an emergency contact.
People with a latex allergy should inform their doctors, dentists, and other healthcare providers about their allergy. Some patients are advised to carry an anaphylaxis kit (containing epinephrine that can be injected under the skin) as a precautionary measure. (See “Patient information: Use of an epinephrine autoinjector”.)
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem.
This article will be updated as needed every four months on our web site (www.uptodate.com/patients).
Related topics for patients, as well as selected articles written for healthcare professionals, are also available. Some of the most relevant are listed below.
Patient Level Information:
Patient information: Atopic dermatitis (eczema)
Patient information: Psoriasis
Patient information: Poison ivy
Patient information: Barrier methods of birth control
Patient information: Use of an epinephrine autoinjector
Professional Level Information:
Approach to the patient with a scalp eruption
Contact dermatitis in children
Dermatitis of the vulva
Overview of dermatitis
Poison ivy (Toxicodendron) dermatitis
Latex allergy: Epidemiology, clinical manifestations, and diagnosis
Latex allergy: Management
The following organizations also provide reliable health information.
- National Library of Medicine
(www.nlm.nih.gov/medlineplus/ency/article/000869.htm, available in Spanish)
- American Contact Dermatitis Society
- American Academy of Allergy, Asthma and Immunology
- Gupta AK, Bluhm R. Seborrheic dermatitis. J Eur Acad Dermatol Venereol 2004; 18:13.
- Saary J, Qureshi R, Palda V, et al. A systematic review of contact dermatitis treatment and prevention. J Am Acad Dermatol 2005; 53:845.
- Sussman, G, Gold, M. Guidelines for the management of latex allergies and safe latex use in health care facilities. Am College of Allergy Asthma and Immunology. Available online at www.acaai.org/public/physicians/latex.htm (Last accessed May 23, 2007).