Contact Dermatitis

Contact DermatitisContact dermatitis describe a rash that is due to a substance coming in contact with the skin. Some of these reactions are the result of an allergic reaction, but many are the result of a non-allergic, or irritant, reaction. Often, it is difficult to tell the difference between these two types of reactions., although there are some differentiating factors.

Irritant contact dermatitis is the result of an offending agent that actually damages the skin with which it comes into contact. The longer the skin is in contact, or the more concentrated the agent, the more severe the reaction. Soaps and detergents is the most common cause. Thus, it is not surprising that these reactions appear most often on the hands, and are frequently work-related. Individuals with other skin diseases, especially eczema are most susceptible.

Contact DermatitisQ: What are the symptoms of contact dermatitis?
A: Allergic contact dermatitis is characterized by an itchy, red, blistered reaction. Unlike irritant contact dermatitis, which occurs within minutes of coming into contact with an offending agent, allergic contact dermatitis reactions can occur 24-48 hours after contact. Once a reaction starts, it takes 14-28 days to resolve, even with treatment.

Q: What can cause contact dermatitis?
A: Agents that frequently cause allergic contact dermatitis include nickel, perfumes and fragrances, dyes, rubber (latex) products and cosmetics. Some ingredients in medications applied to the skin also can cause an allergic reaction.

Contact DermatitisQ: What is the treatment of contact dermatitis?
A: Treatment of irritant contact dermatitis include avoidance of the incremented agent. Gloves can sometimes be helpful. Since these reactions are non-allergic in nature, treatment is directed toward relieving symptoms and preventing any permanent damage to the affected skin.

Treatment for allergic contact dermatitis depends on the severity of the symptoms. When the rash is limited to small areas of the skin, topical corticosteroid creams may be prescribed to offer relief. When large areas of the body are involved, oral corticosteroids may be prescribed. If prescribed, it is important to continue to take oral medications for the entire duration of the reaction. To prevent the reaction from recurring, make sure to avoid contact with the offending substance. If the doctor cannot determine the agent causing the reaction based on the patient's history, the allergist may do a patch tests to help identify it.

Please refer to the section on skin testing.