Contact Dermatitis
Quotes from Epstein, "Poison Ivy/Poison Oak (Rhus Allergy)", Common Skin Disorders (Ed 2), 1983.

Contact Dermatitis is inflammation of the skin due to direct or indirect contact with a substance.

ETIOLOGY
"Acute contact dermatitis in North America from poison ivy (East & Midwest) or poison oak (West) is exceedingly common. Poison ivy/oak dermatitis is an example of allergic contact dermatitis. The allergens in poison ivy, poison oak and poison sumac are similar, and the clinical manifestations and treatment are essentially identical. These plants all belong to the genus Rhus."

"Rhus dermatitis results from skin's contact with the plant’s oleoresins. The patient may have come into direct contact with the plant or indirect contact with the oleoresin, which can be carried on fur of a pet, on clothing or hands, or via smoke. The allergen is not spread by wind or air."

TREATMENT
"Treatment of Rhus dermatitis consists of suppression with corticosteroids. Corticosteroids provide dramatic relief."

"Washing after Rhus exposure is a time-honored preventive measure. Unfortunately, it’s seldom effective. The allergen is rapidly bound to the skin; in order to prevent dermatitis, it’s necessary to wash within 15 minutes of contact. Washing does rapidly destroy the oleoresin, and washing garments or an exposed pet will prevent the indirect spread of oleoresin. Strong soaps and detergents are unnecessary, since the Rhus allergen is unstable in the presence of moisture."

"Desensitization as a method of preventing Rhus dermatitis remains an unrealized dream."

SPECIFIC THERAPY OF ACUTE RHUS DERMATITIS
"Systemic corticosteroids work quickly and can prevent the weeks of blistering and misery that severe Rhus dermatitis causes. Systemic corticosteroids are essential in the acute phase, since topical steroids can’t penetrate the swollen, blistered skin."

"Usually 60 to 100 mg of prednisone a day are adequate; severe cases may initially require daily doses of 200 mg. As the dermatitis improves, the daily amount of corticosteroid is reduced. A 10 to 14 day course of oral steroids usually suffices."

"Prednisone is the preferred corticosteroid."

"Short courses of corticosteroids are safe; it’s prolonged steroid intake over months or years that produces dangerous side effects."

"Antihistamines don’t suppress contact dermatitis, nor are they antipruritic except for their sedative side effects."

TOPICAL THERAPY
"During the acute, swollen, vesicular stage, what the patient doesn’t apply to his/her skin is more important than what he/she does. Topical therapy doesn’t help at this stage. The wrong topical may even aggravate the dermatitis, since anesthetic ointments can sensitize, alcohol and astringents may irritate, and calamine and other lotions make a mess without doing much good."

For more information on contact and atopic dermatitis, go to:  Web Doctor or American Academy of Dermatology.