Contact Dermatitis

Patients with contact dermatitis may report itching, burning, or stinging sensations on their skin. Depending on the type (irritant or allergic contact dermatitis), they may describe exposure to chemicals, cosmetics, jewelry, or new clothing. Individuals with allergic contact dermatitis often experience delayed reactions (24–72 hours after exposure), while irritant dermatitis may present symptoms within minutes to hours. Patients could report a history of occupational or recreational exposure to known allergens like nickel, poison ivy, fragrances, or harsh detergents. Chronic cases may also report persistent dryness or cracking of the skin.

What will it look like? (Examination)

On examination, contact dermatitis typically presents in three phases:

1. Acute phase: Red, swollen skin with blisters, crusting, or oozing. It may look tender or inflamed.

2. Subacute phase: Dry, scaly areas with possible hyperpigmentation and crust formation.

3. Chronic phase: Lichenified, thickened skin with accentuated skin lines.

The pattern of the rash can often give clues to the source of exposure. For example, in allergic contact dermatitis, the rash often develops at the site of direct contact, such as under a bracelet or around the waistband, while in irritant contact dermatitis, it often appears on hands or forearms. Additionally, photo contact dermatitis may show on sun-exposed areas of the body.

How can you help? (Treatment)

Treatment of contact dermatitis involves avoiding the triggering substance:

• Avoidance of irritants/allergens is key. Patients should be educated about the offending agents and instructed to protect their skin (e.g., wearing gloves for chemical exposure, avoiding nickel-containing jewelry).

• Topical corticosteroids (e.g., clobetasol propionate 0.05% or 1% hydrocortisone ointments) are effective for reducing inflammation in more severe cases. High-potency steroids should be avoided in thin-skin areas (face, genitals) to prevent side effects like skin atrophy.

• Antihistamines (e.g., hydroxyzine or cetirizine) may help alleviate itching.

• For patients with chronic or recurrent symptoms, emollients can help maintain skin hydration.

• Tacrolimus or pimecrolimus ointments, which modulate the immune response, can be useful in allergic contact dermatitis.

• If photo-allergic: sunprotection (sunhat, long sleeves, high collar).

• In severe cases, systemic corticosteroids might be necessary, with a gradual tapering of dosage to prevent relapses.

For patients exposed to poison ivy or similar allergens, early washing with soap (within two hours of exposure) is essential to remove the allergen from the skin.