Contact dermatitis: Symptoms, Causes, Risk Factors, Contagiousness, Complications, Diagnosis, Treatment and Prevention


Contact dermatitis is a red, localized rash or irritation of the skin caused by direct contact with a inducing substance to which the skin reacts or an allergic reaction to it.

May 31, 2018

Contact dermatitis is a red, localized rash or irritation of the skin caused by direct contact with a inducing substance to which the skin reacts or an allergic reaction to it.
This condition occurs when you come into contact with certain substance that cause a reaction. Such substances are toxic to the skin and are termed primary irritants. Others may induce an immunologic reaction called allergic contact dermatitis and include plant oils, metals, cleaning solutions, cosmetic additives, perfumes, industrial chemicals, topical antibiotics, and latex rubber additives.
Most contact dermatitis reactions aren't severe, but they can be unpleasant until the itching goes away. You need to identify and avoid the cause of your reaction in order to treat contact dermatitis successfully. The rash usually clears up in two to four weeks if you can avoid the offending substance. You can try soothing your skin with cool, wet compresses, anti-itch creams and other self-care steps.

Symptoms of Contact dermatitis:

The symptoms of contact dermatitis depend on the cause and how sensitive you are to the substance. It usually occurs on areas of your body that have been directly exposed to the reaction causing substance. The rash usually develops within minutes to hours of exposure and can last two to four weeks.

Allergic contact dermatitis:

Symptoms associated with allergic contact dermatitis include:

  • dry, scaly, flaky skin
  • hives
  • oozing blisters
  • skin redness
  • skin that appears darkened or leathery
  • skin that burns
  • extreme itching
  • sun sensitivity
  • swelling, especially in the eyes, face, or groin areas

Irritant contact dermatitis:

Irritant contact dermatitis may cause slightly different symptoms, such as:

  • blistering
  • cracking skin due to extreme dryness
  • swelling
  • skin that feels stiff or tight
  • ulcerations
  • open sores that form crusts

See your doctor if the rash:   

  • is uncomfortable and disrupting your sleep or distracting from your daily activities
  • is sudden, painful, severe or widespread
  • doesn't get better within three weeks
  • affects your face or genitals
  • is feeling you embarrassed by the way your skin looks
  • You need immediate medical care in the following situations:
  • If you think your skin is infected. Symptoms include fever and pus oozing from blisters.
  • Your lungs, eyes or nasal passages are painful and inflamed. This can be due to inhaling an allergen.
  • If you think the rash has damaged the mucous lining of your mouth and digestive tract.

Causes of Contact dermatitis:

Contact dermatitis is caused when you are exposed a substance that irritates your skin or triggers an allergic reaction.
Some of these substances may cause both irritant contact dermatitis and allergic contact dermatitis.

Irritant contact dermatitis:

This is the most common type of contact dermatitis which occurs when the skin comes in contact with a toxic material. The outer protective layer of skin will be damaged by non-allergic skin reaction. Some people react to strong irritants after a single exposure. Others may develop signs and symptoms after repeated exposures to even mild irritants. And some people develop a tolerance to the substance over time.
Common irritants include:

  • Solvents
  • Rubbing alcohol
  • Bleach and detergents
  • Shampoos, permanent wave solutions
  • drain cleaners
  • kerosene
  • Airborne substances, such as sawdust or wool dust
  • Fertilizers and pesticides
  • Plants

Allergic contact dermatitis:

Allergic contact dermatitis occurs when the skin develops an allergic reaction after being exposed to a foreign substance or allergen that triggers an immune reaction in your skin. This causes the body to release inflammatory chemicals that can make the skin feel itchy and irritated.
Usually only the area that came into contact with the allergen get affected. But it may be triggered by something that enters your body through foods, flavorings, medicine, or medical or dental procedures which is called as systemic contact dermatitis.
Strong allergen such as poison ivy can affect your skin after a single exposure where as weaker allergens may require multiple exposures over several years to trigger an allergy. Once you develop an allergy to a substance, even a small amount of it can cause a reaction.
Common allergens include:

  • Nickel or gold , which is used in jewelry, buckles and many other items
  • Medications, such as antibiotic creams and oral antihistamines
  • Plants such as poison ivy and mango, which contain a highly allergenic substance called urushiol
  • Formaldehyde, which is used in preservatives, disinfectants and clothing
  • Personal care products, such as deodorants, body washes, hair dyes, cosmetics and nail polish
  • Balsam of Peru, which is used in many products, such as perfumes, cosmetics, mouth rinses and flavorings
  • Airborne substances, such as ragweed pollen and spray insecticides

Products such as some sunscreens and oral medications that cause a reaction when you are in the sun known as photoallergic contact dermatitis. Children can develop this condition from the usual offenders and also from exposure to diapers, baby wipes, sunscreens, clothing with snaps or dyes, and many more.

Risk Factors of Contact Dermatitis:

Most common risk factor is exposure to normal or damaged skin to irritating chemical or known allergens. Less irritating materials like soap or even water can be a risk factor. People whose hands are frequently exposed to water, such as hairdressers, bartenders, and healthcare workers, often experience irritant contact dermatitis of the hands.
Common solvents used in the workplace can damage the skin, producing an irritant dermatitis and permitting allergens access to the deeper tissues. Some jobs and hobbies put you at higher risk of contact dermatitis. Examples include:

  • Health care and dental employees
  • Metalworkers
  • Auto mechanics
  • Construction workers
  • Hairdressers and cosmetologists
  • Scuba divers or swimmers, due to the rubber in face masks or goggles
  • Gardeners and agricultural workers
  • Cooks and others who work with food
  • Cleaners

Contagiousness of Contact Dermatitis:

Since contact dermatitis is not caused by an infectious microorganism, it is not contagious. However, the condition can produce open raw skin leading to a secondary infection on the damaged skin. This secondary infection can be contagious.

Complications of Contact Dermatitis:

If you repeatedly scratch the affected area, contact dermatitis can lead to an infection causing the area to become wet and oozing. The bacteria or fungi can grow there and may cause an infection.
The most common types of infection are staphylococcus and streptococcus. These can lead to a condition called impetigo. This is a highly contagious skin infection. However, most infections can be treated with antibiotics or antifungal medication.
Scratching can make your skin even itchier which can lead to chronic scratching and scaling. As a result of this the skin may become thick, discolored, and leathery. This can be treated by using corticosteroid creams, anti-itch medications, and anti-anxiety drugs. Streptococcus or staphylococcus bacteria can also cause Cellulitis which is another complications of contact dermatitis. The symptoms of cellulitis include fever, redness, and pain in the affected area. Other symptoms include red streaks in the skin, chills, and aches. It can be life threatening if you have a weakened immune system. Oral antibiotics can be used to treat cellulitis.
Contact dermatitis can also affect your quality of life if the symptoms are severe, persistent, or cause scarring. They may make it difficult for you to do your regular task or may also make you feel embarrassed about the appearance of your skin.
You should talk to your doctor about how to manage your symptoms more effectively in these conditions.

Diagnosis of Contact Dermatitis:

Contact dermatitis can be diagnosed and its cause can be identified by a doctor by talking to you about your signs and symptoms. He/she may question you to find out clues about the trigger substance, and examining your skin to note the pattern and intensity of your rash.
Blood tests and X-rays are not helpful in diagnosing contact dermatitis. A patch testing can be done by applying chemicals or potential allergens to adhesive patches, which are then placed on your skin for 48 to 72 hours in an effort to reproduce the eruption. Skin reactions under the patches can be checked by the doctor to determines whether further testing is needed. This test can be useful if the cause of your rash is not apparent or if your rash recurs often.

Treatment of Contact Dermatitis:

Most cases of contact dermatitis go away on their own without any treatment once the substance is no longer in contact with the skin. However, you should seek medical attention if your rash is close to your eyes or mouth, covers a large area of your body, or doesn't improve with home treatment.
Medications that are most often prescribed by doctors include:

Steroid creams or ointments:

These  are topically applied creams or ointments that help soothe the rash of contact dermatitis. A topical steroid may be applied 1 or 2 times a day for 2 to 4 weeks.

Oral medications:

Oral corticosteroids may prescribed in severe cases to reduce inflammation, antihistamines to relieve itching or antibiotics to fight a bacterial infection.

Here are some tips you can try at home:

  • Avoid scratching your irritated skin. Scratching can make the irritation worse or even cause a skin infection that requires antibiotics.
  • Clean your skin with mild soap and lukewarm water to remove any irritants.
  • Stop using any products you think might be causing the problem.
  • Apply bland petroleum jelly like Vaseline to soothe the area.
  • Try using anti-itch treatments such as calamine lotion or hydrocortisone cream.
  • Take an antihistamine drug such as diphenhydramine to cut down on itching and to reduce your allergic response if required.

Prevention of Contact dermatitis:

Avoiding initial exposure to irritants can help prevent contact dermatitis. Using products labeled as hypoallergenic or unscented are safe.
The following general prevention steps can help prevent contact dermatitis:

  • Avoid irritants and allergens. Try to identify and avoid substances that irritate your skin or cause an allergic reaction.
  • Wash your skin thoroughly. You might be able to remove most of the rash causing substance if you wash your skin right away after coming into contact with it. Use a mild, fragrance free soap and warm water. Rinse completely. Also wash any clothing or other items that may have come into contact with a plant allergen, such as poison ivy.
  • Wear protective clothing or gloves. Face masks, goggles, gloves and other protective items can shield you from irritating substances, including household cleansers.
  • Apply a barrier cream or gel. These products can provide a protective layer for your skin. For example, an over-the-counter skin cream containing bentoquatam or ivyblock may prevent or lessen your skin's reaction to poison ivy.
  • Use moisturizer. Regularly applying moisturizing lotions can help restore your skin's outermost layer and keep your skin supple.
  • Apply an iron-on patch to cover metal fasteners next to your skin. For example, this can help you avoid a reaction to jean snaps.
  • Take care around pets. Allergens from plants, such as poison ivy, can cling to pets and then be spread to people.
  • Avoid wearing latex gloves if you have a latex allergy. Opt for vinyl gloves instead.
  • Always do a spot test with any new products if you have sensitive skin. You can test the product by applying it to one place on your forearm. Cover the area, and don't expose it to water or soap. Check for any reaction between 48 to 96 hours after application. Don't use the product if there is any redness or irritation.