Contact Dermatitis

Contact dermatitis is a rash caused by direct contact with a substance that either irritates the skin or causes an allergic reaction within the skin.  Although the rash is not life-threatening, it can be very uncomfortable.  
 

Many different substances can cause contact dermatitis as we will talk about below.  Recently, many people have developed contact dermatitis as a result of frequent use of hand sanitizer.  I thought this would be a timely topic for our discussion this week.
 

What are the signs and symptoms of contact dermatitis?
 

Symptoms usually occur in areas that have been directly exposed to the irritant or allergen.  For instance, with poison ivy, it would be the area that came into contact with the plant or oil from the plant.  Hand sanitizer would most commonly cause symptoms on the hands.  
 

Here are the things to look for: 

• A red rash, which may include bumps and blisters
• Blisters may develop oozing and crusting
• Itching, which can be quite severe
• Cracked and scaly dry skin
• Swelling   
• Burning sensation
• Tenderness

What causes contact dermatitis?
 

Contact dermatitis can be caused by two different types of substances.
 

The first type is irritants.  Irritants are substances which damage your skin's outer protective layer.  Sometimes people react to a strong substance after one exposure.  Other times, the reaction develops after repeated exposure to milder irritants.  

Here are some common irritants:

• Products containing rubbing alcohol, including hand sanitizer
• Solvents
• Bleach and detergents
• Hair products, including shampoos, hair dyes, or perm solutions
• Fertilizers or pesticides
• Sawdust
• Wool, or wool dust

The second type of substance is something that causes an allergic reaction within the skin.  Something that causes an allergic reaction is called an allergen.  This allergic skin reaction usually only affects the skin that was directly exposed to the allergen.  But it can be triggered by something that you eat or drink, such as foods, food dyes or flavorings, or medication.  It is also possible for something that contacts the skin in one area to cause an allergic reaction in the skin all over the body.  Sometimes you may react to an allergen the first time you are exposed, but you can also develop an allergy after multiple exposures over several years.  
 

Here are some common allergens:

• Nickel, found in jewelry, belt buckles, and many other items
• Plants, such as poison ivy
• Medications
• Formaldehyde, found in disinfectant, preservatives, and some clothing
• Balsam of Peru, used in many products from perfumes to mouth rinses
• Personal care products, such as deodorants, cosmetics, nail polish, etc.
• Products that cause a reaction when your skin is exposed to sunlight, such as some medications and some sunscreens.

Are some people at higher risk for contact dermatitis?
 

People who have certain hobbies or jobs are at higher risk simply because they are exposed to more of the possible causes.  These include:

• Health care workers
• Metal workers
• Construction workers
• Hairdressers and cosmetologists
• Auto mechanics
• Cleaners
• Gardeners, farmers, and agricultural workers
• Cooks and others who work with food

 Are there complications that might occur from contact dermatitis?
 

The primary complication is infection in the skin, which is not uncommon if you repeatedly scratch the affected area.  Scratching damages the skin and allows bacteria or fungi to grow.
 

Next week, we will talk more about prevention and treatment of contact dermatitis.  

If you have any questions about contact dermatitis, please log into your account and send us your question. We are here to help.

Dr. Anita Bennett MD - Health Tip Content Editor