Understanding Contact Dermatitis

Contact dermatitis is a rash that occurs when something touches and irritates the skin (dermatitis—referring to a condition of the skin). Contact dermatitis is not fatal or even very dangerous, but it is usually extremely uncomfortable. Here is a look at potential causes, symptoms, and treatments of contact dermatitis.

Irritant Contact Dermatitis Causes

The rash that forms in irritant contact dermatitis is caused when your skin comes into contact with a substance that irritates it. This may be because of what the substance or item is made of, or because so many things can become irritable and develop a rash on the skin if given enough time. 

The reaction can happen with just a few seconds of contact; in other situations it can take extended contact (i.e. several applications of a type of makeup or years of using the same soap). Common causes of irritant contact dermatitis are diapers (diaper rash) or chemicals (acid burns). Even water can irritate the skin through excessive hand washing or licking of the lips, which often causes dry, cracked skin. 

According to the Mayo Clinic, other causes of irritant contact dermatitis include: 

  • Solvents
  • Rubbing Alcohol
  • Bleach
  • Personal Care Products
  • Airborne Irritants (sawdust, etc)
  • Burdock

Allergic Contact Dermatitis Causes

Triggers for allergic contact dermatitis are different for everyone. Essentially, contact dermatitis can occur just by coming into contact with something you’re allergic to. This could be a plant or an ingredient in a skin care product. As the name suggests, brushing against the skin is sufficient—generally the rash remains around the area that touched the allergen. Common instigators include: 

  • Nickel
  • Pharmaceuticals (particularly antibiotics or antihistamines)
  • Balsam of Peru
  • Formaldehyde
  • Skin care and other hygiene products (deodorant, makeup, lotion, nail polish, etc)
  • Tattoos
  • Airborne substances, like aromatherapy sprays, or
  • Insecticide

The symptoms of contact dermatitis can appear through ingestion of food, medicine, or via dental work. This causes “systemic contact dermatitis” (an immune reaction is triggered by the substance). Some substances may cause a reaction when the skin comes in contact with the sun in a condition referred to as photoallergic dermatitis. Occupational contact dermatitis refers to contact dermatitis specifically acquired while working. Some vocations have a higher rate of contact dermatitis, such as working with plants or insecticides or cleaning chemicals.

Symptoms

Again, contact dermatitis is not fatal, but it isn’t pleasant either. In just a few minutes or hours after the substance is touched (or ingested, in the case of systemic contact dermatitis), a rash begins to develop at the site of contact and may be visible for up to a month. In addition to the red, bumpy rash, you may notice your skin feeling very itchy. The area may become swollen, feel like it’s burning, or become sore to the touch. Severe reactions may develop blisters, leak pus, or appear crusty. Chronic contact dermatitis may leave the skin dry and scaly. 

Treatment and Prevention

Unfortunately, very little can be done for contact dermatitis. In most cases, the rash can be dealt with from home—although if you aren’t sure it is contact dermatitis, medical assistance isn’t a bad idea. The first step to both treatment and prevention is to stay away from whatever caused your reaction—which means figuring out what triggered your dermatitis. If you are prone to developing contact dermatitis, skin repairing medications (like calcineurin inhibitors tacrolimus or pimecrolimus) can help repair and prevent reactions long term—however, be sure you know the side effects of these medications. Bad cases of contact dermatitis may require prescription medications like steroid cream, oral corticosteroids, or antihistamines.